Corpse Killer is probably the best looking FMV game on the 32X CD. Unfortunately I don't have the regular non-32X version so I can't do comparisons. But here are two others:
NIGHT TRAP:
The Sega CD version uses between 40-50 colors onscreen for the entire game. The 32X version runs at around 300 colors onscreen.
Not the best looking 32X CD game, that's for sure.
FAHRENHEIT:
The video is much larger and the Sega CD version puts between 30-40 colors onscreen at a time.
The 32X version puts over 400.