hax or fun?
I recently figured out exactly how to do Hunter wall jumps in L4D. It's really FUN, though i have yet to figure out how to use it to do much damage (i accidentally jumped off the ceiling once i think...)
It might be a good match for skulks. Not infinite hopping around, just something to change direction or surprise people. In l4d, it works by hitting a wall, swinging the camera around, and re-jumping in a "correct" direction. Different engine, so it would need to be added in, but it would allow a skill-based maneuver for advanced skulks. If you could bounce out of a vent, hit an opposing wall, and spring off to backstab a too-slow marine who's attempting to cover the vent. Or get shredded by turrets, or catch a shotgun to the face, whatever. No-one says you have to do it either.
Angles, speeds, and other details are obviously open to balancing and such, but it's an idea. Ohey, not even on a search for "wall jump" either.
Onos should not be able to wall jump.