The only reason Peter would be better than Hope in power replication, this is saying that he can even copy the powers of Hulk and Sentry, lies in the sole fact that he would also have Sylar's powers. This means he could copy your powers and then instantly master them, maybe even using them to a degree better than you can.
Does it bounce energy? I thought it just absorbed it? But even if the energy of the initial contact was absorbed, what I see happening is; Superman now has he fist on the shield and is pushing it with all his might. So while Cap might take no damage from the punch itself, he'll definitely go flying. That explains why in several of those scans he took the blows with no injuries but was still lifted off his feet, especially with Cyclops. Cyclops's beams generate concussive force. Because of that, the shield can absorb the beams initial force, but after that, the force that the beam still carries as a whole will push Ca[ back. Am I making sense? lol