Hi!
I played Aliens for some time now and have one major problem:
When I crawl on the wall or ceiling, Tremulous pushes my view around a lot. It automatically moves my view even if I only crawl over a small wall-feature(small pipe, etc).
This disorients me much usually. Sometimes I am not able to find the floor or ceiling anymore, because I sit in a somewhat dark edge (alien

) and when I move I automatically am "attached" to another wall or small feature and thus only turn around.
My suggestion: Add a sense for gravity to the aliens, so they always know where down is. This could eg. be achieved with an arrow pointing down when the alien is in wall-crawl mode. (Like the damage direction indicator.)