Aight, I've updated my roster for (hopefully) the last time. I added Dixie, Palutena, Chrome, Dark Samus, and Adam Malkovich, bringing the grand total to (a pretty unrealistic) 60.
I really don't feel that we'll be seeing THAT many characters, but I do think that seeing anyone outside of this list will be pretty surprising.
In order to bring it down to a more realistic 50, I'd probably drop, in no particular order
Toad, Roy, Dixie, Palutena, Adam, Ray 01, Lucario, Krystal, Mii, and Bandana Dee.
As much as I'd hate to drop ANY of these characters, these 10 stick out as some of the more unlikely, at least to me. If anyone wants, I can explain why, but the current image as it is stands as more of a Dream Roster than a realistic one.