I'll try to put this into perspective with a rhetorical question. Let's pretend for a moment that there are no Capcom characters in Smash, and you had to choose the first one. Would it make more sense to go with Mega Man, Ryu, or Amaterasu? (Amaterasu could be replaced with another Capcom character from a series that you're more familiar with)
Okami is an extremely good game with a passionate fanbase, but you can't deny that if a Capcom character's going to be added, Mega Man and Ryu (in either order) would make the most sense given how huge and influential Mega Man and Street Fighter are as series. Same thing goes for Phoenix Wright, Monster Hunter, Dante, or whoever else you might be familiar with - it's going to be extremely difficult to justify putting them in before Mega Man and/or Ryu.
Now that Mega Man and Ryu are in Smash, the third Capcom character that you chose has a much better chance of making it in - there doesn't seem to be a clear front-runner among that group. Same thing goes for Geno - he's got an extremely passionate and dedicated fanbase, which seems to give him the edge over other Square-Enix characters (Sora's owned by Disney, so I'm not sure if he counts as a Square-Enix character), but it wouldn't make much sense to include him over two of the biggest and most influential RPG series out there.