Kawaiiii Uguuuu ~
Alright, it's been a long while since I've gone full ******, and I thought I'd throw out some feels I have about character chances. Of course, I'm doing it tier style. Before I jump into newcomers, let me start with vets.
Everyone from Brawl will return without a doubt, besides these characters:
Possibly Being cut From Brawl
Ike, Wolf, Sonic, Snake, Toon Link, Lucario, Pokemon Trainer
Now, I don't believe all of these characters will be cut. Heck, the only one I'm dead sure on is Snake. But I will say Lucario, and Toon Link are good candidates for cuts. Sonic would be in that group if it wasn't for the fact that Sakurai has already mentioned his sheer popularity once more. Next would be Sonic and Pokemon Trainer. Then least concern would be Wolf, and Ike.
Now, Newcomer Tiers:
Best Chances
Mewtwo, Dixie Kong, Chrom Pac-Man, Miis, Little Mac
The first three pretty much go without saying IMO. They each have a strong quality going for them. Mewtwo being who he is, the publicity he's recently gotten, Sakurai's comments, his position as an old vet and as popular as he is. Dixie's a once planned character, and a decently popular choice. Chrom is an international character from FE, who's in the latest FE title, and is generally well received (despite what Smashboards would like you to believe). The last three, well, you know.
Decent Chances
Roy, King K. Rool, Ridley, Palutena, Shulk, Takamaru
The first two would be up in the "Best Chances" group if it wasn't for their Franchise counterparts taking precedence IMO. Ridley's here for being a small scale Mewtwo. Palutena, for being a popular choice, Sakurai's baby, and showing up in SSE/Brawl. Shulk kind of beats out all his competition, with Miis/Little Mac being the acceptions in terms of small franchise character. He's pretty popular for how old he is, and seems to be the new "IT BOY" from Nintendo's new star subsidary. Takamaru fits the role of "Retro revived" pretty well, and has a recognizably sized fanbase in both Japan and America.
50/50 Shot
Doctor Mario, Krystal, Bowser Junior, Samurai Goroh, Black Shadow, Lucina, Isaac, Toon Zelda / Partner
Doc and Toon Link / Partner are like Dixie, but just on a smaller scale. They have an alright sized fanbase, but also seem to be filler material, unlike Dixie. Krystal, Junior, Isaac, Goroh, and BShadow is the all around "Got Everything, just it's up to Sakurai to say yes". Lucina seems to be like the former, just, she has Chrom and Roy in her way.
Small Chance, but still worth mentioning
Toad, Paper Mario, Waluigi, WarioWare Employee, Ghirahim, Tingle, Bandana Dee, Zoroark, Genesect, Other 6th Gen, Dark Samus, Medusa, Masked Man / Claus, Lyn, Pikmin Trio, Starfy, Dillon, Mach Rider, Layton
Instead of saying what these character's DON'T have, I'll throw out their best traits. Toad: Seniority, Iconic Paper Mario: Decently Popular Waluigi: Decently Popular, WarioWare Employee: Interesting / Wario's alone as of right now Ghirahim: Interesting, Popular enough, Personality Tingle: Interesting Zelda's Number 4 Bandana Dee: Interesting, Kirby's Number 4, Zoroark: Interesting, Most Popular Pokemon Choice Behind Mewtwo, Genesect: Mewtwo's Rival, 6th Gen: Hey, it's 6th Gen, Dark Samus: Not Big, Clone Material. Medusa: Big Villain, Decently Popular, Masked Man / Claus: Next in Line for Mother, Personality Lyn: Decently Popular, Interesting. Pikmin Trio: Hey, who knows?, Starfy: Small Franchise with Decent Popularity, Dillon: See Starfy, Mach Rider: Takamaru's Number 2, Layton: If there's any third party that isn't Sonic, Pac, Mega, or Snake, it's him.