I could add boxes or some other form of cover, though, I was planning on having the vents allow the smaller aliens to bypass this particular open area. That, and the lower section is going to be accessible to the alien players, though, I haven't decided if I'm going to put a func_ladder in there for any marines who feel the urge to jump down there.
So far, I've tried to keep the unwanted visible faces of the map (in com view) to the sides as much as possible. So far, I'm hoping that the clutter isn't too bad:
