From Nintendo, I think Little Mac, Daisy and (who knows?) the Mii (?!) will be included.
From third-parties, perhaps Mega Man (CAPCOM is doing well with Nintendo now), but I wanted Amaterasu to be included.

I'm hoping for Knuckles, Tails, a return of Solid Snake, Raiden, Little Mac, Mega Man, Zero, Travis Touchdown, Professor Layton.

Nintendo: Little mac, dark samus or any MPH hunter, and i ant mewtwo back!
Third Party: Geno (not sure if this counts as first or third party), Travis Touchdown, Jack (Madworld), and please zack from zack and wiki(not sure what abilities you would put on him.

Man, their are so many characters I'd like to see duke it out in there. I'll just make some honorable mentions:

- Terry Bogard (since he simbolizes SNK's cross-over games, why shouldn't he in Nintendo's cross-over franchise, now that Orochi Saga is on a Nintendo console)
- Ryu Masters/Megaman (wich ever represents Capcom)
- Princess Daisy (I can see her using chinese boxing moves)
- Mewtwo (Just bring him back)
- Female Pokemon Trainer (we got a male one, why not the other gender)
- Kristal (like the others said, there's to many Fox clones)
- Young Link (Toon Link was a nice touch, but I like the original)
- Tails (If Sonic returns)
- Knuckles (same as above)
- Kat and Ana (Plays like the Ice Climbers)

Hopefully the ones that run smoothly online.

I made a thread about this a wild back. But, people weren't too envious of it because it was too early i guess.

http://www.vgchartz.com/forum/post.php?id=2600771

I just want this 3:

Megaman
Kratos
Ryu (SF)

Ludwig Von Koopa

It'd be interesting to see what characters won in a poll tbh.

I honestly hope that no Party 3 characters are in the next one.

Nintendo:
Little Mac
Louie(Pikmin)
Baby Bowser
New Pokemon Trainer(Replace the old one with new pokemon)
Tom Nook(Animal Crossing)