I finally had enough time to look at this again, and there are quite a lot of improvements. Lighting is better, detailing is better, and the whole thing looks and feels really polished. The only things I noticed that were out of place were the flat gray textures at the top edge of the green and yellow bases which some skylights might work better for (and some more passages to red/blue space on the mid level would be nice too). Otherwise, this is a great map