I'm leaning towards Ashley being playable. It would be a great curveball, because it seems _nobody_ is expecting that.
Also, can you imagine the boss of a FIGHTING game being a little girl?
Well really, if every franchise gets a boss or something along those lines in Adventure Mode, I don't see anyone else who would really fit better. If they decide to really focus Wario moreso at WarioWare rather than Warioland, as shown by his outfit (although it would seem odd if we don't get the option of his classic purple and yellow), WarioWare doesn't *quite* have a villian.
Aside from Wario himself stealing profits, Ashley seems more like the only real candidate I can think of off the top of my head as a WarioWare "villian", considering she's just somewhat questionable and sadistic. That, and she DID try to cook Orbulon, and then even little ol' Red
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However if Ashley is playable I wouldn't be upset one bit, I like her in an odd way.
Anyway back on topic: I really don't see Jimmy T. as a fighter. I was really hoping for him to be the "Goldeen" of Assist Trophies but it seems Resetti stole that spot (nevermind, I like the little mole too ^_^). Also, why is Jimmy T. using a blasted cellphone for his Final Smash? If anything his character SCREAMS massive stage-wide disco light show. ANYTHING disco related, but really I don't see the phone suiting what should be his ultimate attack when disco is a much more integral part of his personality.