Okay, let me get you started on the Fox vs. Peach matchup. I'm sure you have an okay idea of how it's done, I'm just going to make some points.
-Shoot lasers at her when she's at least 1/2 Firefox away from you, if she gets closer..it's probably too risky
-Do not, I repeat DO NOT ever try to uair Peach when she's on a platform above you. It's just not even worth the risk of being dsmashed like that
-Peach will be outprioritizing your aerials in almost every scenario, so don't clash with her in the air
-Dair->Waveshine->Upsmash if she ever gets above your target percent; why deal damage you don't need?
You're pretty good, work on your techskill (as always), work on your mental game (as always). Keep up the good fox.