Fellow vita lover here. The homebrew scene is top notch and still amazingly active. I haven’t gotten around to setting up retroarch (it’s on my to do list!) but I’ve played some nes/snes on standalone emulators and they mostly work well, though I have noticed some audio artifacts on some games. OCing the CPU and enabling frame skipping seems to help with those, though. But overall, I’m still thrilled with the device.

If you haven’t tried it, Touch My Katamari uses the back touch screen and it’s quite fun. I agree it’s really not needed but occasionally someone does something fun with it.