I think most people that have commented already have the right idea. The Hand Cannon needs to be separate from the scout rifle more, and it needs to play to its strength..which should be manoeuvrability. I would make it a specialised hip fire weapon, more damage so that head shots are less important then your movement speed while shooting, giving it the advantage over the autos. Maybe even the ability to fire while you are ascending with the double jump/lift/glide to give it the real manoeuvring edge.