Heh, you're giving me too much credit... you saw how drastically my skill with Dedede collapsed after playing everyone else- he's a different character, for sure, and zerowing likely won't make the same mistakes I do. Against Dedede though, I'd recommend trying to keep close- Dedede outcamps Peach, but in close range she has a DEFINITE speed advantage, which forces Dedede to retreat. I recommend using QCQ the most against Dedede.
Glad to hear those were the best games you've played, I certainly enjoyed myself as well and it gave me some much-needed experience against Peach, so hopefully Dunk won't beat me as soundly next time.
In terms of tips, I'm not quite sure what to recommend... you mixed up your ground and air games pretty fluidly, so it was hard to keep up 100% of the time. I did notice you stopped using Peach's upsmash and tilt, which I'd say are pretty handy killing moves. Hmm... yeah, overall I'd say you did well. Just focus more on dodging, I guess? A lot of the time when you were recovering you just moved right into my egg toss's line of fire, you often had plenty of time to airdodge safely but didn't. Otherwise just keep up the good work, HG.