Not as bad as I thought. Only watched part of the first match.
FC your aerials, and float more in general, especially against Falco. Going just above the lasers seems to freak out most Falcos, and gets them to try and fight you in the air, which doesn't always work for him.
Uthrow to dsmash. Don't EVER uthrow to usmash. Closest you should ever get to that is uthrow to rapid fc uair combo at about 40% or so. Even then, a CG works better for most.
You seem smart enough, just work on variation and consistency. Early deaths are game killers for Peach. D:
Don't fsmash to edgeguard. FC nair, bair, dsmash, or even turnips and a simple edgehog are WAAAAAAAY better options. Sure, the tennis racket is great, and the golf club is okay, but if you get the frying pan, you have to start all over again.
EDIT: Don't use the Peach Bomber or Toad for anything aside from off the stage recovery/sweetspotting help. Only Vidjo can use it to put people into bad situations. D: