I am no way a top peach player, but I'd like to put my two cents in here. Playing Peach is similar to playing any character really, you pick the character up and play them to the best you can. The difference with Peach and other characters is as you previously mentioned is Peach's overall complexity and her reliance on her most unique ability floating. This in my opinion puts her in an awkward position where she's only good in the right hands, and those hands are hard to find. That isn't to say that there aren't people who play Peach at a high level, (SlayerZ, EOE, Umeki, Yaaay, and Dark Pch come to mind) but overall it's much harder to play her. Nevertheless the top peach players are pushing the character to her limits, and I think Peach will do the same thing she did in melee. She'll eventually rise in the tiers as we begin to figure her out fully, and take advantage of every AT she has to offer. (Provided they don't get patched out like TLC was) I think she'll be a tournament threat hopefully sooner rather than later =)