Gosh, I feel like a failure of an Amigan for saying this, but: the only work of his that I've heard is Railroad Tycoon, Frontier, and Beneath a Steel Sky. Never played any of the other games.
That being said, all are phenomenal. It's only since the ScummVM era that I learned that the tracks on the PC version of Steel Sky are actually longer (I'm guessing due to assumed lack of RAM in Amigas circa 1994), but the orchestrations on the Amiga version are so vastly superior, even compared against top-tier modern MIDI renditions. I still find myself humming bits of those tunes on a regular basis. I wonder if he has "complete" versions of the Amiga tracks in his archive somewhere?