Right, so less than 6 hours to go, who is everyone (other than staff and @Glen\-i)hoping for?
Here are my top 4:
Captain Toad
Captain Toad has managed to make the Toad species interesting again (sorry Toadsworth) and with the moves from Super Mario 3D World & Captain Toad Treasure Trackers, he would make an interesting character. They'd have to make him able to jump, sure, but make him like Little Mac and be a terrible jumper.
Bomberman
Bomberman is an amazing character with a long history of Nintendo. While Konami are seemingly not doing games anymore, they did just put out a Bomberman mobile game and Bomberman would be the last(ish) third party character that I'd really accept in the game
Hoopa
Hoopa is a bit flavour of the month, but thanks to the fact it uses rings as portals, it has so much potential as a fighter, being able to call in elements etc. to do combat. Plus, its Final Smash could be it turning into Hoopa Unbound and doing this.
I would say Hoopa Unbound should be the fighter, but it's Ridley levels of big.
Finally, and a massive outlier. Jibanyan
Yo-kai Watch is HUGE in Japan. Seriously, huge, and while its popularity there is dying down (merch sales in the summer were down 75% on last year and the anime keeps switching ratings with Pokémon rather than being ahead) and it didn't make an impact in the US, Jibanyan would be a cool option in here. It can use its Soul Link attacks very well. Personally, I'd have liked Whisper, but Whisper isn't really a fighting Yo-kai
I think Inklings should wait until the next Smash. There are lots of other Nintendo characters I'd like in Smash, but let's save something for the next one, eh?
Who do I think we'll see? Impossible to say. Dixie, K. Rool, Shovel Knight (urgh) are all solid choices