I'm not completely sold on Dante, but maybe that's just because I don't want him. But a lot of times a dev will retweet about an upcoming direct or something, and it turns out to be nothing. Could be just a coincidence that they're planning on making an announcement about DMC on the 16th.
Still holding out hope for Geno personally. We've gotten a lot of third party DLC characters, so I'd like the last one to be someone with a stronger connection to Nintendo. But, maybe they're holding off on characters they own for the next Smash game.
Just about everyone relevant they own is in the game already as either a fighter or assist trophy, who else is there to add? The only way for Smash to keep expanding into relevant new territory as things stands is bringing in more third-party franchises.
An ARMS rep, a Golden Sun rep, Dixie Kong, Rex, Pyra, Elma, Impa, Paper Mario, Captain Toad, Chibi Robo, Midna, Krystal, Ring Fit Girl/Boy, Agent 8 are just a few that pop into mind.