Alright so! Pushdustin seems to think that the translation for the whole "New Worlds" section was Sakurai commenting on how it was incredible they could open whole new worlds by adding a single character rather than "Yo the next batch of characters? Also all third party or from new Nintendo IPs"
Rumour is ten additional characters. Pick your poison! Who would you choose?
For me personally I'm currently here:
All Nintendo:
Captain Toad/Toad with Toadette alt
Dixie Kong
Bandana Waddle Dee
Impa
Meowth
Akira Howard(Astral Chain)
Chibi Robo
Isaac(Golden Sun)
Waluigi
Vaati(Zelda)
All Third Party:
Chris Redfield(or Jill Valentine)
Crash Bandicoot
Spyro
Heavy(Team Fortress 2)
Lara Croft
Tails
Rayman
Chun-Li
Gordan Freeman (Half Life)
Conker
Personal ideal mix:
Captain Toad/Toad with Toadette alt
Dixie Kong
Bandana Waddle Dee
Meowth
Impa or Vaati
Waluigi
Chris Redfield
Crash
Spyro
Heavy
Remember back when I posted my toad moveset idea. I'm still having trouble thinking up moves for Toad. I still want to give him Mario's neutral and up sepcial moves to make him a pseudo clone of Mario, but I can't think of anything else besides that.
This is going to be quite long, so apologies, but I have so many ideas for Toad it's kinda nuts:
Since we're discussing Classic Toad, he's known for a few things; the items guy and the speedy one. Maybe build your new Toad moveset around his speed?
He's known for being a grappler in SMB2 and Wario's Woods, heaving enemies much larger than him over his head and running with them without slowing down at all. I'd personally give him the ability to pick up an enemy and run with them similar to Donkey Kong to represent this. You could combine this with speedy use of power ups in a similar vein to Piranha Plant changing it's look for certain attacks.
Some examples:
Side B to transform into Cat Toad and launch yourself forwards, slashing with your cat paws as you do so.
Down B to transform into Builder Toad and pluck up a building block that you can run with to stop opponents movements(or to just give Toad an additional projectile)
or Side B to transform into Builder Toad and run forwards with a hammer/pickaxe(as a reference to Captain Toad's Super Pickaxe item)
Down B to transform into Tanooki Toad and slam down into the ground as a Tanooki statue.
or Side B to transform into Penguin Toad and do a sliding tackle into the enemy, knocking enemies flying
Down B to place a Spiny shell atop your head, allowing you to negate attacks from above for one hit.
or go full Mario Psuedo clone and have:
Side B to transform into Cape Toad(Mario Maker 2 gives him this ability). This move works differently from Mario's in that Toad spins forward wearing the cape. The attack can deflect projectiles(same as Mario) but it doesn't flip opponents around, instead dealing damage.
Down B to spew spores. Works like FLUDD with less of a pushback but deals damage.
Sakurai seems to think Toad is suited to a grappler style too between his new found use in Peach/Daisy's moveset, his Mii fighter being a Brawler and his Spirit Battle being all about grappling.
Alternatively Toad is also known for being one of a large species. Perhaps the ability to summon other Toads to aid you in battle could be interesting be it either Toad Brigade members or the Double Cherry item that he uses in Super Mario 3D World AND Captain Toad Treasure Tracker.
Lastly Toad has had his own games in which he kicks bombs across the floor, throws turnips, rides minecarts, destroys blocks and enemies with pickaxes and even runs up walls like gravity doesn't matter to him. There's plenty of fun stuff you can do, you just need to know what you want the focus to be for him.
One good thing about Toad is he has several interesting avenues to go for: Do you go for power up Toad? Speedy rush down Toad? Do you focus entirely on mushroom abilities like mega mushroom giving him power, mini giving him speed, propeller mushrooms giving him great recovery and throwing poison mushrooms at enemies? Do you perhaps focus on the fact Toad is part of a plentiful race and is known for it? Do you use him as the Mario Kart rep and focus on the power ups and speed from that ala Captain Falcon or Fox? Do you use his role as Mario Party's host to give him a RNG filled madness moveset? So many options, so little time!
I hope that helps you at least a little!