I'll do my best to answer your questions here, as my interests were very similar when I decided to purchase my PLAY!
1/ Personally, I don't think so. It's the only phone which has the slide-out game pad, and especially the touchpads. There is a N64 emulator (allowed to name it here?) which supports the touchpads, and I believe FPSe may be getting touch pad support when ICS is released officially (correct me if I'm wrong, not trying to spread false information here!)
2/ There are a fair few different compatibility lists around the internet, and to be honest from my experience I've often had more luck running some games than I expected!
The most reliable list I usually check on is here: http://forum.xda-developers.com/showthr ... ?t=1034472
I've not tried any of the games you've listed yet, but I'm more than happy to try them and report back if you want
3/ I've got various emulators installed on my PLAY now including GBA, SNES and Genesis and I can't say I've had any issues at all with them.
Overall, I'd say the PLAY is a fantastic choice if your main focus is gaming and, more specifically, emulation