There is talk of an "Interior Design Mode" for FPSC-R which I would assume would be like you talked about having the ability to hide building roofs. You can easily script a health re-gen system, and same as "blood splash screen", the Q and E "peek" keys where removed from fpsc and I think most people didn't like them, however there should probably be an option to enable it if you wanted to.
Prone would be nice with the new terrain system but should be disableable too.
Intel(R) Core(TM) i7-3820 CPU @ 3.60GHz; 16GB RAM; NVIDIA GeForce GTX 680 2048 MB; Microsoft Windows 8