Semi joking of course but yep, it is very possible there's just more than we think simply due to having more time to work on the actual game.
Just been thinking about how they shocked us in May with the "Everyone is Here!" and how most of us thought even that was impossible. I personally think the "Ultimate" title also includes newcomers, in that Ultimate will add more newcomers than any other game (including echoes). But it's a personal thought that I'd never argue with anyone cause it sounds ridiculous like "every character returning" did for years.
My theory is that "Ultimate" means that this time around, nobody is left behind. Not just vets, but glaring holes are going to be plugged across the board.
Just think about it:
* Ridley and K. Rool rounding out some of the more notable villains, with the latter doing so incredibly conspicuously.
* Chrom filling out the core Awakening cast.
* Dark Samus explicitly representing the Prime series.
* Daisy being added so you could "play as your favorite Princess."
* Simon Belmont adding to the classic NES icons, with Richter there to showcase how the Belmonts have evolved.
* Lots of assist trophies from pretty much every series.
I really think this is going to be the game where villains and side characters shine. We're going to see picks like Isabelle, Ken, Tails, Skull Kid, Shadow, Geno, Elma, and all the rest rather than pulling in tons of new IPs and honestly I think it's better off for it. This looks to be the comprehensive Smash in every sense of the word.
I expect quite a bunch.