my idea about UT theme is one big building with a "garden" in its center with one huge and few regular trees, maybe some little lake with waterfall, a bunker or other kind of army structure and some sewerage-like close-combat spaces. Player could use 4 elevators to reach top of the structure and also inside of central tree could be an elevator. I think that concept like this might provide long, medium and close distance opportunities with interesting terrain.
I did not created this picture, but I have something like that in my mind:
Sorry for my bad English.