I have read the multiple threads on this board about multiple screens set ups - but as is often the case my scenario is slightly different 

I have a XPS 13 9360 with a Dell Adapter DA100 – USB 3.0 to HDMI/VGA/Ethernet/USB 2.0. I have a Dell P2717H monitor connected via HDMI from the DA100. I am also using the DA100 for Ethernet. The monitor also acts as a USB hub for my wired keyboard and  webcam. 

I want to add a second external monitor. I still have to decide what size - may be a 24 or 27 or 32 inch. I have decided that if it is a 24 inch then FHD will be fine - but if it is a 27 or 32 inch then at least QHD will be required because I want the dpi to always be above 90. 

I would appreciate some help to understand what my options are - it seems to me that I have two options

1) but a 24 inch FHD monitor that allows DisplayPort chaining from the new monitor to my current monitor. Will the USB hub still work in my P2717H?

2) but a hub - not sure which one. Seems like the DA100 would not help anymore?

I may want to add a fourth screen in the medium term - but I am not sure how many screens the XPS 13 9360 with Intel's 620 GPU will be able to drive. I do not play games with this machine - only work so refresh rate at 60+ is fine