Wow, your peach seemed pretty solid. It seemed like it was all there, but I think you'd benefit from just speeding it up a little. If you just tighten up your offensive game I think it'd help end their stock a lot more solidly.
Also, your defensive game seemed a little sub-par compared to your onstage control. Try working on nair OoS and stuff like that, it becomes killer vs falco and really in every MU. It seemed like as soon as you shielded, you tended to just go kind of panic mode and make bad judgements and dsmashes.
Asides from that I just really liked the way you controlled space. It seemed like whenever you were in control you kept him scared, and whenever he tried to come into the center you kept him out and punished effectively.
Finally, I think something you could add to your game (and most other peaches could too) is fair to grab. Seemed like you'd drop on his shield with fair and dsmash every time. While this is dandy and stabs almost all the time, it seemed like you followed up from your grabs really effectively, while when you got a dsmash, it was either just 14% or a ledgeguard. It's framesafe
You grabbed most when it seemed like you wanted a grab. Grabs work the best not when you want it, but when they really don't want to get grabbed. You went for it by the ledge and when you weren't in control, and as you seem to really gain control when you get a grab, that makes sense, but if you fair to grab on shield then that might help you tighten up your offensive game.
Good luck :D
Also, is that the Cobalt who went to RoM? I played him, he seemed alright.