Seems a bit too basic for me to judge right now, especially in the collision department. Yes, you do collided and stop/slide with objects, but you seem to stop way to far away. I walked into a wall and there was still about a foot of space before actually touching it. Maybe shrink the bounding box or use a physics engine for perfect poly to poly collisions...
Also, is it just me or do you walk/jump way to slow? (It may be me, I have like 2 other 3d programs on.)