I'd suggest some Unreal Tournament 2004 map but there doesn't seem to be any easy way of converting them to use in a regular 3d editor.
Actually, holy crap, your work is inspiring. It's surprising to see that anyone at all is still working on the whole 3d thing, keep up the good work. After looking at your results I thought I should give it a shot as well. Unfortunately even though I'm quite experienced at programming in general my knowledge of 3d models is close to zero. Gotta use the Google power.