Peach has one of the best arial games/attacks out there (Jiggly Puff being first and all)
Let me see if I can find a proper 5150 response for this... can't find one exactly... This is what he'd say anyways.
5150 said:
In depth overanalysis... skip is recommended...
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Take a look at the characters-generally peach's fair will beat a lot of these moves, but who's going to attack you when you're fairing?:
Doc: uair and bair beat every aerial peach has--dair from above does the same so does fair.
Mairo: uair bair and dair beat all of peach's moves.
Luigi: goes even with peach as far as aerial priority
Bowser: most of his moves beat yours... but that's why you don't attack him when he's attacking.
Yoshi: gets owned ^^
DK: gets owned ^^
CF: beats your aerials when he picks the right moves
Ganon: has a better aerial game
Falco and Fox: Yea, they win aerial priority battles.
Ness: Fair beats all you have flat.
Icys: If they could space their moves, they'd win
Kirby: gets owned too
Samus: even
Sheik: wins 90% of priority battles
Zelda: likes to outspace you
Link/Ylink: Hello disjointed hitbox. Plus nair is always suprising.
Pichu and Pika: lose (yay!)
Jiggs: Big fat win for jiggs
M2: gets owned
Gdubs, Marth and Roy: disjointed. hit. box.
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To sum up, I count 6 characters peach outprioritizes consistently in the air. 2 that she's pretty even with, and the rest
beat peach in the air-assuming they're using the right moves.
Peach needs to DI to get out of combos. Nairing only works when the other person isn't fast enough to keep you stunned-but it's still not a bad idea. Know when peach's stun time ends so if the opportunity is there you can take it.
If you're tired of falling for fox's uthrow to uair, learn to smash DI.
If you're tired of getting spiked by Marth, DI awaaay. Or buy Pal and meteor cancel.
If you're tired of getting nair comboed into a knee by CF, smash DI the nairs.
Peach's priority is in her ground moves. Not in her aerials.
Let me reiterate that:
Peach's aerial priority is mediocre.