Had a good run around, it's a nice and simple fast layout that I can't really fault.
Got some ideas that were running through my mind while i was wandering around, some pics with with cheesy red highlights
(clicky for big) :
You've used this texture quite a lot, it really stands out and loosk out of place to me because of the deep shadows on the texture not reflecting the actual lighting,
I love this idea, but the symmetry of it takes away the impact. You could clip round the circular part on the bottom ledge and move the lights onto the ceiling so they are still aligned with the little circles on the texture.
This corridor feels very cramped and narrow, you could widen it and open up the windows to give players somewhere to hop in and out of cover quickly when there's somebody on the ledge above them.
I can see you didn't add the central pillar to these because it would be in the way of the steps, you could make some nice decorative arches or such at both ends to separate that part out from the rest a bit and add a bit of interest.
These ledges feel very narrow and cramped when moving about on them, you could widen the areas outwards to give more room on them or even widen them inwards to give an overhang to provide cover to people on the bottom level.
The top level outside feels very small and squat compared to the grandeur and size of the interiors and the lower level.
You could build up some interesting stuff outside of the playable area like cliffs, pillars, walls, trees and more foliage etc (gargoyles?
). These would let you cast some sexy shadows onto the playing area when you revisit your light_env and you could really go to town on the brushwork as it wouldn't get in the way of players.
Looking forward to your next update