The best choices on the list

Steam
Knights of the Old Republic. It's rare for me to say this, but being dated makes it a bit hard to play. It's still a good game though.


PS3
Mass Effect Series. Seriously, start at 1.

PS2
Zone of the Enders 2nd Runner. An enjoyable game.

PlayStation
Your choice

PSP
No experience here.

Wii
Or here

GameCube
Skies of Arcadia. I enjoyed it way back when. Maybe it's still fun?

N64
LoZ: Majora's Mask

SNES
Tactics Ogre. Not entirely sure here, just a hunch.

3DS
Bravely Default (Once you finish 4 Heroes of Light) By reputation alone.

DS
Finish one of the half dozen games you started... like Revenant Wings or DQIX.

Sega Stuff
Can Shadowrun be put on this list? It's the greatest Sega game. I may have bias from my pen and paper Shadowrun days.