Exactly as said: Who do you want in the inevitable WiiU Smash sequel? Let's forget about the characters meant for Brawl but kept out (Dixie, Toon Zelda/Shiek, Plustle/Minun, ect), beceause they're probably going to get in.

I'd personally like King K. Rool, preferrably using his blunderbuss from DKC2 and his heli-pak from DKC3 for his B moves (Because, he's a great villain, and if Bowser and Ganondorf can get in, so should he) and Duster Because, since Ness/Lucas stole so many of Paula/Kumatora's moves, and Jeff is already only an assist trophy, I think he's the only Earthbound/Mother character with a unique moveset they could use.

I'd also love to see Captain Syrup from Wario Land (Because she was Wario's best villain, hands down), Little Mac (I Do not get why he was only made into an assist Trophy) Mike Jones (Because, since Star Tropics is pretty obscure, he'd be a great wild card), Sukapon (Same reason, just repalce Star Tropics with Joy Mecha Fight) and The Eggplant Wizard (Because, come on, he's way more iconic Kid Icarus villain than Medusa, you know it)

I'd also love to see actual Nintendo villains as antagonists of the story mode instead of some original creations, as the whole reason we wanted the story mode was to fight through hordes of the unique enemies of each franchise instead of some Heartless knockoffs.

Specifically, the bosses I'd liek to see are:
King Bulblax (Pikmin)
Titain Dweevil (Pikmin 2)
Kraid (Metroid)
Queen Metroid (Also Metroid)
Mother Brain (Guess.)
Genesect (Pokemon)
Mr. Sandman (Punch-Out)
King Hippo (Punch Out)
Tiki Tong (Donkey Kong Country)
Rudy the Clown (Wario Land)
King Boo (Super Mario Bros)
TOm Nook (Animal Crossing, with a mecha made out of his store)

And with either Giygas, Majora's Mask or O2 as the Big Bad, because they're likely the only ones creepy/powerful enough to work well (Though I think it would be O2 because Sakurai DID create Kirby).

But, what do you folks think?