I just rewrote the vertical movement system which works fine now. Basically I used USE_BOX, and made the c_trace start from the middle of the entity, and have it's z size be as much as the entity. This way, the 2 ellipsoids (the bounding box, and the c_trace) would basically make a rectangular box on the bottom.



Blue = Bounding Box
Red = c_trace

It's obviously a bit more complex than that (some bugs showed up), but I took care of it all. The only problem I have with this method is that if the player jumps, he can climb up ledges which are a tad high, but all that does is get rid of the need for a crouch jump, which I'm willing to sacrifice.

Thanks for all the help!