That's a really hard question
I guess, if you're one of those FF-music types, you'll probably be able to say Uematsu.
But I'd say the composers I've had the consistent most respect for over the years (as opposed to say, a flash in the pan or once-off great score) would be the Falcom musicians (Sound Team JDK). It may sound like a copout, but they've covered nearly every genre with their arranges, and shown (for my money) that VGM doesn't have to fit any stereotype or particular genre. I love that.
At the moment, I've been listening to some once-off's, like Inca 1/2 (Gilles Douieb), Pitfall: The Mayan Adventure (David Kneupper), and others. Those guys are scary talented. Sadly they didn't do much game music.
Oh, of course, Motoi Sakuraba deserves a mention. Geez, I've played so many games he's worked on. Even if I don't like the game (Star Ocean), I love the music!
Regards,
- Spike
Jam it back in, in the dark.