I think the envisioned use case was that the user would simply place the dock behind their laptop.  Of course that would obstruct the USB ports on the front of the dock, but maybe that's why all of the marketing photos show laptops with their lids closed and only external displays in use?  Another option would be to get some sort of platform that's wide and deep enough to support a laptop and leaves enough clearance underneath it to support the dock.

As for the cable length, there's a partial explanation for that.  18" is the longest passive Thunderbolt 3 cable that can support the 40 Gbps throughput that this system requires.  There are "active" cables that can extend that longer, but they cost about $80, and some of those won't carry the amount of power that these docks are marketed to be able to provide for attached Dell systems.  The reason I said that was a "partial" explanation is because even if a customer was willing to spend that kind of cash on a longer cable and found one rated to carry the required amount of power, it turns out that the dock side of that cable attaches with a proprietary connector, not a standard Thunderbolt connector, which makes replacement with aftermarket options impossible.  I suppose that may have been deliberate precisely to avoid problems getting customer complaints and negative reviews saying, "This dock doesn't work" when the true cause is that the customer is trying to use it with the wrong cable, but for those of us who would've known the right product to buy and would have been willing to spend more, it is a frustrating limitation.

And just fyi, it's not entirely true that the TB16 is the only option for modern laptops.  There's also the WD15 dock, and since I have one, I just measured its cable at 30".  The catch there is that since it just uses regular USB-C rather than Thunderbolt, it only supports dual 1080p displays, whereas the TB16 supports dual 4K and even some triple display configurations.  The WD15 also doesn't support "upstream" Thunderbolt peripherals like the TB16 can, if you have any of those.

We've had a couple WD15s and they were an unmitigated disaster of a product. I actually replaced two of them with the TB16 because both WD15s were so unreliable. They would randomly drop video, USB ports would stop working, and they had trouble waking laptops from sleep. For a while I kept updated the firmwares and BIOS of the hardware involved in an effort to fix it. I replaced WD15s with more expensive TB16s and was initially thrilled with their performance (especially compared to the buggy WD15s) before I realized the cable length limitation.

When we upgrade the laptops, we also have upgraded users to higher resolution monitors which the WD15 doesn't support anyway.

Reading around the forums it appears the WD15s have a ton of problems and my experience was not uncommon.  That really only leaves the TB16 as the single dock option for the new Dell laptops.

Another issue with this TB16 (and the WD15) is that unlike the E-series laptops, the user has nothing to "click" their laptop into. They have to literally just find some space on their desks (within 18 inches of the dock of course) to put their laptop. I actually have removed the E-series port replicator from the Dell under the monitor docking solution and put skid pads on the remaining plastic part so the user can at least lay the laptop on the empty dock plastic.

It's a really crappy solution and my users are not thrilled with losing desk space. I'm not thrilled because it seems so half-assed to just tell my users "Uh, I guess just shove some stuff around on your desk and put your laptop, uh somewhere back there I guess, but remember it has to be almost right next to this new black box oh yeah, and make sure you don't bend that connector in a goofy way because it may eventually break the USB-C port on your laptop".

Shame because I love the new Dell Latittude 15" and 14" laptops. Just without a way to properly dock them I am considering switching vendors. We loved the old E-series because of the docking solution, because users could click into a port replicator and it was reliable and just worked without screwing with this 18" cable and having users rearrange their desks. Now that there's no decent docking solution I'm not tied into Dell as a vendor because HP doesn't have a great docking solution either.

Ah yes, based on your latest post and looking at your username, I seem to remember having a long discussion with you about these docks a while ago.  Well if the TB16 is the only option that meets your technical requirements, then you're basically stuck for now.  I suspect Dell will release a new TB dock based on Intel's new Titan Ridge controller architecture though.  One of the main advantages of the chip intended for peripheral devices (as opposed to the PC) is that it allows Thunderbolt peripherals to fall back to regular USB-C when used with PCs that don't support Thunderbolt, though of course functionality would be reduced -- but that's better than not working at all, I suppose, which is the case now with the TB16 and any PC that doesn't support Thunderbolt.  Perhaps at that point Dell will design their dock with a standard Thunderbolt cable, in which case they could be replaced by active Thunderbolt 3 cables rated for 5-amp Power Delivery.  StarTech makes one that's 1m long, if you're willing to spring for it.

As for the desk placement issue, I actually see it both ways.  First, the WD15 and TB16 are a smaller overall footprint than a full E-Dock, but more importantly I actually kind of LIKE the fact that the location and orientation of your laptop isn't dictated by the placement and orientation of the dock.  Granted there's more freedom with the WD15 thanks to the longer cable length, but for example it allows the dock to be kept along the rear edge of my wife's desk while the laptop itself is closer to her in case she wants to use its built-in display while docked.  And then the other major boon in her use case is that her personal PC is a Dell, but her work PC is a Lenovo, and having a WD15 gives her a single docking station that works with both systems, whereas before she'd have either needed to keep two large docks on her desk and swap USB and display cables back and forth between docks as needed (or get a KVM, which is even more desk space lost and of course cost), or simply never dock one of those systems.

Actually, rereading that reply, I guess I don't really see it both ways.... How do your users have less desk space now than they did with the E-Dock?  I get the idea that they can't physically lock their laptop in somewhere, but whether they use an E-Dock, a TB16, or a WD15, they still have a laptop sitting on their desk and a dock behind it.  With the older E Series laptops that had their underside docking connectors closer to the center, the E-Dock's rear protrusion I suppose is a bit shallower than the WD15 or TB16, but the E-Dock is also quite a bit wider, so I guess it depends on the dimensions of the desk.  But on the newer Latitude Exx40 models, the underside docking connector is along right along the rear edge of the system, which means there's practically no overlap with the existing E-Dock "tray", which in turns causes the E-Dock to add several inches of depth to the total desk footprint of dock and laptop solution.  What am I missing here?

I'll take some pictures of the user's desks and see if I can do a before/after thing to show you how the desk space is lessened. A couple of my users just deal with it, and a couple of them complain about it. The main issue is that the laptop itself is say, a 15 x 12" square, and docked with the under-the-monitor docking solution, lets say it took up 18 x 18", but it was all "self contained" under the monitor for lack of a better term. Now, the laptop has to balance on top of the empty plastic without the e-dock, or if I get rid of the under the monitor docking plastic, it kind of half balances on the plastic monitor stand. Or, the laptop has to move to a different space entirely on the users desk to "lay flat".

The TB16 is a box that sits to the left side of the laptop, because if you put it behind the laptop you lose access to the ports on front of it. If the cable was longer or you could swap the cable from right/left of the TB16, it'd be a bit better because I could place it between the two monitors. Instead it always has to hang out on the left side of the laptop. It sounds minor ("always on the left side of the laptop") and I play it off when I deliver the laptop to the user, but two weeks later they gripe about it and ask "Can I just get a longer cable so I can put it over here instead?"

And yes, I definitely recall our long chat about this! I do appreciate you steering me in the right direction, I have had both docks for a few months now and my complaints about it may seem picky but considering the price of these docks and how IMO they're sunk by this cabling issue. Especially considering how the E-port docks (and the docking solution before that) had this docking problem completely solved for many years.

My biggest concern as the IT guy isn't users complaining about desk space, it's the stress on the TB3 connector on the laptop. Because of the way you have to wrap that cable from the left side of the TB16 to the left side of the laptop, it's always pulling and stressing the TB3 port on the laptop. The TB16 cable is also a fairly thick gauge so it's not that flexible. Knowing how users connect and reconnect all the time I can see that port getting yanked around.

I have had success with for dual-monitor setups is using articulating arms to hold the monitors instead of them on monitor stands. The arm solution reclaims desk space (no more plastic under the monitors) so I may move the complaining users in that direction. 

Ok, I missed the part about you using the monitor stands that are specifically designed to have E-Docks slotted under them.  I'm familiar with them, but I hadn't seen them for a while.  Now I totally get it.  I have one suggestion on the off chance you haven't thought of it, although I'm betting you have.  Assuming the TB16's greater depth compared to the E-Dock doesn't prevent it from being placed in the dock area under the stand completely behind the laptop, I realize that its front USB ports would be obstructed, but the E-Dock obviously didn't have front-facing USB ports either, so is that situation a dealbreaker?  The E-Dock did have side ports though, which of course the TB16 doesn't.  If those side ports were used frequently, then are you perhaps using displays that have built-in side USB ports that might be able to make up for that loss by running a USB cable from the display down to the dock, at least for the people who don't want the TB16 off to the side?

With respect to the cable, believe me I'm familiar with the fears that exist in IT people based on users who do all sort of crazy things! :)  For what it's worth, the cable is actually replaceable separately, since there are screws hiding under a rubber insert underneath the attachment point on the dock (all detailed in the TB16's manual on support.dell.com), but I haven't looked at how easy it is to buy just that part, and again it would have to come from Dell since the dock-side connector is proprietary rather than standard TB3.

Articulating arms are definitely a godsend from a desk space standpoint.  It's amazing how much real estate even regular display stands take up these days, but articulating arms are also a bit expensive and somewhat of a chore to install the first time, especially if you want to route the cables neatly -- and sometimes you need to buy longer cables in order to run along the entire length of the arm before dipping down to the dock, otherwise you risk the cable preventing certain arm positioning.

Anyhow, it sounds like you've already got the only dock that meets your technical requirements, but as I said, given the announcement of Intel's new Titan Ridge controller, you may see a TB17 dock or whatever Dell ends up calling it sometime this year, and maybe that one will use a standard dock-side connector and therefore allow replacement with longer, active cables.  If you go that route, just make sure they support 40 Gbps throughput AND are rated for 5 amps or 100W Power Delivery.  Dell pushes the standard a bit to 130W, but since that's not an official rating of the USB Power Delivery spec, I doubt you'll find any cables formally certified for that.  Good luck!

I've given up on the TB16 and I've bought a few of these Caldigit TS3's which are working out great so far:

https://www.amazon.com/gp/product/B07CZPV8DF/ref=oh_aui_detailpage_o00_s01?ie=UTF8&psc=1

There are a few downsides:

• They also do not have a very long cable. However -  unlike the TB16 - the cable it comes with is detachable, and if need be, you can spend another $50 to get the longer TB3 Active cable.
• They only have a single Displayport connector and I can't seem to daisy chain them. However we have purchased $20 USB-C to HDMI cables and those work great for connecting another monitor.
• There is no power switch on this device, so to wake up a closed lid / sleeping laptop, you have to enable the "Wake on USB activity" option in the BIOS. This is an option on any of the modern Dell TB3 enabled laptops in the Power area in the BIOS.
• I don't think they actually deliver 85w of power, more like 68w. But the laptops don't yell about an undersized power supply and it all works fine. 
• Multiple 2.5ghz Wifi keyboards/mice seem to be goofy with them and the manual specifically states that if you use multiple devices you should get an cable extender or an external hub. Don't have any idea why this is the case. We solved the problem by plugging the wifi devices into our USB ports on our monitors, and then plugging the monitor USB into the Dock.

Compared to the upsides:

• So far, they just plain work. No goofy USB drop outs like we had with the TB16, no wacky firmware update process, no need for some giant wasteful 240w power supply just to charge a 14" ultrabook.
• While they're kind of industrial looking, you can stand them up or lay them horizontally.
• They work with Apple laptops as well so you can standardize a mixed PC/Mac environment.
• You're supporting a company that has thought this through instead of just buying whatever half baked buggy e-port dock replacement that Dell is selling.

I agree with the design of the cable coming out of the left side. Seems like an easy solution to that would have been to possibly make it adjustable. I have a medium to smaller desk and I like the device but the cable does not hinder how I use it or where I place my laptop. I slide my laptop under my screen riser and the dock on the screen riser so it all aligns. After years of products and chasing electronic wants and needs its hard to be so critical about something that just works. I am about 9 months into this dock and I only touch it to clean the dust off.  Having two 32 inch 4K HDR  monitors running together at 60Hz I shall not complain. I have only just got the current configurations running over the past days so plenty of time to fail I suppose but if it runs as smooth (which it is for now) as it did with the 1080 monitors then I will love it. I pull the Laptop all the time and it just plugs back in and everything works. I dont have an open port on the entire dock except 1 USB on the front and the two HDMI slots on the back. I also use a 7 port USB 3 power hub plugged into the back where I have my Keyboard and mouse plugged in and it just works, a long with other devices such as Skype phone ect... While I am not disagreeing with you and can see how the design could drive some crazy it seems to push others to Avoid is a bit strong for a device that works well for certain needs that can otherwise difficult to obtain.  

My problem is also the cable connector. I have this docking station at home and work and am constantly "docking and un-docking". At work I am always aware of the where the connector mates with the laptop and how I need to not twist or move or jostle or press down on the very long, yet very narrow connector for fear of breaking the connector or damaging the port. I am always placing my laptop in such a position as to not put any undue stress on the connector. Why you say? Because I have already broken the one I have at home! The plastic cover snapped off not long after the warranty expired (of course). Both the cable and port still work, but I think I was just lucky in that respect. Laptops are supposed to be mobile. Why, oh why design something that is this long, narrow and delicate if it is going to get a lot of wear and tear?

Every singe one of my TB16s has that broken plastic cover on the connector. It's not a matter of if they'll break, but a matter of when. They're just junky 

I tape them back up with electrical tape, but then it hides the LED that shows when you're connected.

Anyway, just minutes ago I rolled out another another Caldigit TB3+ dock for another user, with two 4k screens. Worked perfectly and I was in and out in 5 minutes. That company has taken my dock business completely away from Dell.

My solution to the TB16 Dock is to TURN THE DOCK UPSIDE DOWN and now your can put the TB16 on the left side of the laptop easily. Though the power or reset button access is blocked but I rarely ever need to press it. And also the usb ports are all now upside down.

Maybe Dell should design their docks so they can be put upside down. So the power button would be on the side and the USB ports all vertical. 

I do want to report excellent success with Dell's new WD19TB dock. Same price and hasn't given me a bit of trouble that the TB16's have. Cable is longer too and it's a flat rectangle instead of a big square. Only downside is that the video capabilities of it are a bit different than the TB16, and I was unable to get a dual monitor setup working by using the DP and HDMI ports on the WD19TB.

I was however able to get two 4k monitors at 60hz working fine by buying DP to USB-C cables and using them with the WD19TB dock.

Interesting that you say Dell show the laptop closed driving two displays. That's how I tried running my XPS15 i9 but found the lid being closed blocks the fan exhausts and so I have to run it half open. The system isn't powerful enough to drive 2 x 4K displays as the advertising says it is. The best I can get is 2 x 2500 with the laptop screen off.  The Dock causes varying levels of hum on my connected HiFi system where as connecting directly to the laptop is fine.  And the other biggie is that occasionally when coming out of a blank screen because the laptop hasn't been used for 20 mins, the screens don't come back on. You can reboot the PC and they still won't come on. The only way to get them on again is to momentarily disconnect the DP connector at the dock. Then all the windows you had carefully sized and placed across the two screen are now on one and of varying sizes. Not impressed at all with the construction, design and even the concept of this .  And yes, I have the latest dock firmware and pc BIOS updates, which is an utter pain to do on the dock as I run Linux Mint, not Windoze. Please give us back connectors on the laptop and a dock firmware upgrade system that doesn't depend on Microsoft. It's really no hardship to reconnect a couple of cables. But it IS a hardship to have to carry two heavy boxes (the dock and it's HUGE power supply) around just to connect peripherals.  And then you get the XPS15 with it's camera UNDER the screen and the screen hinge blocking the fan exhaust. Makes you wonder what the people who designed these systems were smoking!  It's a really expensive and well built system but very poorly designed resulting in a large amount of buyer remorse IMHO.