mame/arcade emulation is a different beast with the newer/better emulators only working with newer romsets.
if a game has trouble in PCSX2 and you just want to play it, rather than play it at higher resolutions, you can enable software mode (F9, I think). if you have a quad core cpu, increase the number of rendering threads. still not perfected, but you get better compatibility and fewer glitches in software mode.
and n64 emulation stagnated years ago and still has its problems. in my experience gamecube/wii emulation is better.
I haven't gotten much into PSP or DS emulators, aside from messing with the android ds emulator. few weeks back people found a way to render DS games at higher resolutions.
about android emulation, today some early videos of dolphin on the nvidia k1 were shown and it runs decently. nvidia shield 2 will end up being a great portable emulation machine.
I'm guessing Valkyria Chronicles 3 & Nayuta no Kiseki are real nice on ppsspp.
do you know if there's any progress on a translation patch for Nayuta?