I think most of us agree that AGA was not quite enough to put the Amiga back in the lead in graphics, but it kept Amigas in the race a lot longer than OCS or ECS could of done if the Amiga had stade at them.
Its a shame that AGA was under used in games but I think some people on here are forgetting that when it was used properly the gaphics blew away what could be on OCS/ECS.

Slam Tilt, Microcosm, Capital Punishment, super stardust, Theme Park, Myst, simon the sorcerer, sim city 2000, gloom, onEscape, napalm etc
Even to this day I still think the best pin ball game in feel, looks and stlye is Slam Tilt, its a MUST for any AGA owner out there!
http://www.youtube.com/watch?v=aXaAfLJuhrs (might have to load it up for a quick go!)