YoshiandToad
Smash Hero
I don't think that the alternate costumes boosts the chances of the Avatar from Awakening. I think that there are other hurdles the Avatar must overcome before he/she becomes playable. (the biggest ones being Roy and Chrom) However, if the Avatar does get in, then I think that we will see both the male and female be playable and alternate costumes of each other.
If nothing else, this gender alt removes Robin's biggest hurdle for NOT being a viable candidate; no defined gender.
Although yeah, Roy and Chrom are the ones s/he'd have to compete with still, and both these sword lords are very popular choices.
Guess this means we can have Dr. Mario back at the very least too! Can't see it working for Young Link or Pichu though unless the name is altered based on the outfit. In which case there's a chance this is how Roy's returning too...not sure how to feel about that.
An Assist Trophy? Still incredibly unlikely. It's the only possibilty other than an alt costume, and even then it's an extremely slim one.
Glad I wasn't the only one thinking this. If it is and he's just positioned Miss Fit to match Sir Fit a lot of us are going to be gutted.