Ok then, sense my original post didn't generate any replies, please allow me to rebuild the query.
I want to emulate the following
NES
SNES
N-64
Gamecube
Sega Master System
Sega Genesis
Saturn
Dreamcast
Gameboy/Color/Advanced
I want to set them up to work through a front end. End goal is a living room box to hook up to the TV so the family can retro out occasionally. What emulators has the BYOAC hive mind had good luck with? I seem to be running into issues with emulators that have GUI's, menu bars, non-standard exit methods, etc...
MESS should be ok for NES, some SNES, Master System, Genesis, some Saturn, Gameboy/Colour. It might not be quite on-par with some of the standalones, but does a commendable job if frontend/cab-friendly is your goal and you like how MAME works. If it runs the games you want in those cases you may as well use it, or UME (which is the MAME compile containing both MAME and MESS drivers)
It definitely won't be OK for N-64, Gamecube, Dreamcast, SNES games using SuperFX, Genesis addons like the 32x, it's just MAME afterall, and you know how MAME struggles for performance on 3D systems (and ones with high frequency support dsps)
GBA might work for some games, but fail on others, it's not very mature.
Saturn your options are limited, like I said MESS is fine for some games (quite a few puzzle games that would work well in a cab run just fine) but lacking in performance in others.. Other Saturn emulators probably aren't going to be amazingly cab/frontend friendly and are a pain to configure (because it's such a complex system)
You didn't mention Playstation, but MESS is actually capable of running a good number of Playstation games well, again including many cab friendly puzzle games and such where you don't really need all the fancy shoulder buttons, analog sticks etc. (There were massive improvements in the emulation around the start-middle of this year)