Replacements:
I think Marth is gone for Ike obvious
Roy will be gone too but for the chick in Ike's game. I played it one time I can't remember her name
Pichu for maybe some other pokemon just to make his spot more fun, because personally I hated him
Dr Mario will return as Paper Mario
Edits and Final Smashes:
I say all characters will return (outside my replacements) with own movesets...
Ganondorf will have a sword and his final smash will be Ganon
I say Young Link stays with the ability to transform into the masks from Majora and final smash is Fierce Diety
Jigglypuff's final smash will have to do with its whole little sing, people fall asleep Mark on faces wake up and realize thing...something like that Nintendo wil work with it
Mewtwo's would be, he get armored up like Giovanni had him and telekensis to the fullest or something like that
New Characters (I'm Certain of):
Wolf (If they have Fox and Falco they need an enemy bring him on)
King Dedede (Technically Metaknight isn't Kirby's supreme enemy so if Link/Mario/and Pikachu have enemies best believe he will)
Baby Bowser (Not only is he Mario's enemy he's Yoshi's enemy and a Bowser associate so it would make sense)
Animal Crossing Guy (I think he will be nameable and an unlockable but he will use his axe(like a sword) slingshot, rod, and net and shovel
King K Rool (Again with 2 DK people they need an enemy)
Maybe Possibly (Might have a chance but who knows:
Sonic (I don't think Knuckles, Tails, or Shadow or anyone else would be in because that would ruin the whole exclusive 3rd party thing)
Mii Characters (Like a create a fighter thing)
Tingle (Japan loves him, he's been in the Zelda series for a while and has his own game, and I heard rumors he was)
Pac-Man (Retro characters rule and I would love him and Game and Watch and Mario to fight)
Lucario (He would be a nice addition like Mewtwo was)
Characters who won't be in IMO:
Ridley (I think he won't be in because he would be awkward to move with(like master hand was if you ever hacked it), he could be a boss though.)
Dark Samus (I played old Metroid's not new ones and by what I've seen from when my brother fights it, it seems like a clone and you can't have that.)
Assist Trophies:
The dinosaur from Ice Climbers: (It would swoop down and get someone and throw them off the stage)
That's all in mind right now..lol tell me what you think