The clue fits Peach at least:
This character is yet another underestimated one, who on the surface seems to be horrible.
Yeah, Peach is currently placing upper-low tier in most people's personal tier lists at the moment. Not to mention some acute nerfing she received from the Melee-Brawl transition - many consider her a poor character.
But in reality, with enough persistance, this character can become a force to reckon with in the future.
This is completly vague and can be said about any single character on the roster. Peach is no exception, if not more fitting.
With a strong long range game
This would be a slight strike against her. Peach has a definite
medium-ranged projectile. Though, being the vague clue that it is, it could be broadening the definition of "long-range" a wee bit. In any case, "strong" would perfectly describe turnips. They're not the best, but counting in glide tossing, z dropping, edge guarding use, and the like, they're pretty great projectiles.
and an awesome aerial game that can open up plenty of combos if you know how to do it right, this character can keep up with the rest.
Everyone knows Peach is awesome in the air - the thing that catches my eye though is the combo thing. Her aerials are amazing, specifically the dair which can usually be done at least twice and then followed by an nair. Juggling with the uair is also nice. Peach easily "keeps up with the rest."
This character's short range game, while at first may seem to be the character's weakest attribute, is actually quite strong if you know how to use it well.
Yeah, unless you space correctly with turnips, her smashes are kinda...
But the trick is to ALWAYS space with turnips - then the smashes are actually quite useful.
Although, the character struggles to get KOs if you don't keep the few KO attacks fresh.
A lot of the cast can live to freakish percentages if the fair or fsmash was used willy-nilly - moderation is the key to KOs with her.
So yeah, I'm not saying it's
sure to be her. But the clues fit - maybe some other characters better. But I look forward to Peach being the next update.