I have the same exact issue. This seems to be an issue with some PCs running Windows 8.1 Pro (Can't confirm for other versions)
I also just purchased a Surface Pro 2, and I have the same issue. WPA-Enterprise and WPA-Personal are no longer available.
I contacted Microsoft and I received confirmation that it should have those two security options for Wireless Networks, and the Microsoft rep has escalated the issue to an Engineer.
I'm to receive a call back in the next two hours, I will update this post with the Engineer's response.