Alright, I think I'll post a roster. I may say some things other people have already said, but whatever. Looking around, I see alot of crazy ideas, and probably will post some of my own, but I'll try my best to back 'em up with reason.
Let's do this.
Mario Franchise
Mario
Luigi
Peach
Bowser
Bowser Jr. - Reasoning here: Bowser Jr. has consistently been a part of the main Mario franchises since his appearance in Sunshine.
He'd be a light character who could have an arsenal of but not limited to: A paintbrush, bombs, a Clown Car (possible up B?) He COULD also have a transformation, but I don't see there being a huge point to that.
As for the rest of the main Mario franchise characters.. I don't think they need an explanation. Without them, all of them, it's not a real Nintendo game, and it's foolish to think any of the four wouldn't be included.
Paper Mario Franchise
Paper Mario
In a game promising to be massive, why wouldn't such a popular and beloved series for over a decade get the main character as a rep, especially considering the new game and possible other new game on the horizon? That plus movesets to hell. Hammers, items, spring jumps dashing, airplanes, and partner ATs. Lots of fancy possibilities.
Donkey Kong Franchise
Donkey Kong
Diddy Kong
K. Rool
Doesn't make sense to cut either of them, nor is there reason to. Both are original characters, one is a 3 game veteran AND a Nintendo icon.
King K. Rool : This is a toughie. K. Rool wasn't in DKCR, but he did appear in spinoff games for the Wii and the peg swingers, most recently he was in Superstar Sluggers (It's..something) However I'm starting to think it doesn't matter, since he's the best choice if they look for a new DK rep, since none of the Tikis stand out, have history, or anything else, and the only Kong besides DK and Diddy present in DKCR was Cranky.
However, I don't think any other characters have even a chance. Maybe Dixie, but probably only if Sakurai wanted to go ahead with that Diddy/Dixie tag team he apparently planned for Brawl.
Wario Franchise
Wario
I don't think this needs to change, but depending on the size of the roster, it could. I've got no suggestions though, not very partial to any of them.
Yoshi Franchise
Yoshi (Yoshi has no chance of being cut. It's Yoshi)
Kamek (I'm putting Kamek here because, well, I like the idea. Not so sure he's not the best chances, but ya never know)
Metroid Franchise
Samus/Zero Suit
Ridley
The thing about Ridley, is it all depends on if they want him to be a boss again. If bosses don't matter, or don't prevent a character from being playable, then he's a shoe-in. About time I think. Size certainly doesn't matter, they can easily make him walk on his hind legs and resize him. I don't even understand how that's EVER a valid argument.
Legend of Zelda Franchise
Tough one here.
Link
Zelda
Ganondorf
Toon/Mask/Young Link
Tingle
These don't need to change, and the series wouldn't be adequately repped without all three pieces of the Triforce. And I suspect ALL of them will be updated to their Skyward Sword models. (Even if it doesn't seem like one or two of them are IN Skyward Sword, also remember Sheik wasn't in TP)
The hard part here is..well, the one or two others. Zelda deserves at least as many reps as Pokemon. Which will probably have 5 or 6.
However, the number of good choices, considering what it usually takes to be in Smash, is pretty slim. They could keep Toon Link, and probably will, give him a new moveset or not. Or they could fulfill my dream and add Mask Link. VERY unlikely.
Tingle.
In all likelyhood, Tingle is probably the most likely choice for a new Zelda Brawl candidate. I know he's not popular with Americans, myself included, but the rest of the world likes him. And even then, it's not their decision fully. He was an AT in Brawl. He might make the jump in SmashU.
So with Zelda, it'll probably be.. The Big Three, Tingle, and whatever other incarnation of Link they choose. Unless they decide to add Vaati too. Or the new villain.
SO LONG ALREADY. JEEZ. DO YOU EVER SHUT UP, ME?
'Fraid not.
Kid Icarus Franchise
Pit
Medusa
I don't know, you'd think Pit is fine by himself, but since Uprising is Sakurai's new brainchild, I feel like it's going to get more love in his next.
And I feel like, to push that, he's going to add another Kid Icarus rep. I'm saying Medusa, but it could be her, Palutena, Eggplant Wizard, or even that guy I don't know the name of who was in the E3 '11 trailer.
Either way, I expect more than Pit. And it's ridiculous to think Pit has any chance of not being in. Although I don't think anyone thinks that...
Kirby Franchise
Kirby
Meta Knight
King Dedede
I don't think Kirby needs anymore reps, if you wanted, maybe Knuckle Joe. And there's no real chance of any of these three being cut out, because again, Sakurai's making the game. Plus, I don't see why you would. They're all very unique. You don't cut characters just to cut them, no matter who they are.
Pokemon Franchise
This one's tough too...
Pikachu
Jigglypuff
Pokemon Trainer
Lucario
Zoroark
I fully see Zoroark making it as the 5th gen rep, no question. I also don't see Lucario being cut, nor anyone else. Why? Because all the other reps are 1st gen. They COULD mix around PT's pokemon, but they won't. They MIGHT add another Pokemon trainer, like a semi-clone, but they probably won't.
With that, there's now (technically 5) gen 1 Pokemon reps playable. That means that if they replaced Lucario with Mewtwo for some stupid reason, there would be 6. I love Mewtwo, but 6 is too many reps for one gen.
Gen 4 was one of their most popular, and Lucario is STILL a very popular Pokemon. He has an original moveset, and isn't Gen 1. There's no reason for him to go. Plus, again, it's a powerful system with lots of room. They'll be adding alot more characters than they'll cut, if any.
Star Fox Franchise
Fox
Falco
Wolf
This is it for me, I don't see this changing. It's unfortunate, but Starfox doesn't have that many viable characters that would be unique in any way. I honestly think these three is the best it's going to get.
F-Zero Franchise
Captain Falcon
Samurai Goroh
Honestly, I'm thinking if they're going to do anything else with F-Zero, it would be bumping Goroh from AT to playable. He was one of the few with a Brawlified model, and could have a unique moveset. F-Zero's fairly dead right now, but that doesn't mean they don't have characters to pull. Falcon's going nowhere, though.
Fire Emblem
Marth
Ike
Gharnef or Black Knight
I'll admit it. I'm not that well versed in Fire Emblem, I've never played a single one. I do know that the two characters in Brawl are the most popular and well-known of the bunch though, and that there are villains to pull from somewhere, whether they be the Black Knight or Gharnef. Gharnef, as I understand, is basically Marth's villain, and I know BK's Ike's.
It'd make sense to use either one of them to round out the series. If they needed to add another. Which, again, new game, more characters, lots more space. Good.
Mother Series
Ness
Lucas
Masked Man
Ness is an original, and Lucas was planned for a while. These guys aren't changin'.
That said, the series is over, but there's still history to pull from. The Masked Man was an interesting character that could provide a twist expected from the "now typical" Mother character in a Smash game. And it's a new game. If it's anyone, it'd probably be him.
Retro Series
G&W
ROB
Ice Climbers
These are all the ones I see as definite...but let's be fun.
Balloon Fighter
Sukapon
They do keep using Balloon Fighter's music. It's something. And Sukapon was one of Sakurai's projects, I've heard that he once stated he's like in the game. But rumors are rumors. And there's lots of Retro WTF characters. (Like a walking Hanafuda card. YES)
Other Series
Olimar
Little Mac
Isaac
Saki
Starfy (The fact that he was in Brawl shocked me enough. He's had a game recently, too)
There's probably more. Olimar's going to be by his lonesome I think, maybe they'll add a Louie costume. But really, there'd be no point in making another playable Pikmin character. Unless the new game has something fancy in it.
Little Mac seems like a yes. Especially since Punch-Out's not retro anymore.
Isaac. Do I really need to explain? He's the Marth of Golden Sun, which also got a new game.
Saki, same thing.
Starfy, same thing.
And finally...
3rd Party
Sonic
Snake
Megaman
These are all subject to the idea that Sakurai asked for 'em. It's also ridiculous to try and add a whole bunch of third parties. Snake and Sonic were a big deal, they got the hell hyped out of them. They're not going to add a total of 3 or 4 new 3rds. Megaman'd be quite enough, really. Maybe I'm wrong.
Alright, well, there's my overly long explanation roster. Now to line em up.
So we've got:
Mario
Luigi
Peach
Bowser
Bowser Jr.
Paper Mario
Yoshi
Kamek
Wario
Donkey Kong
Diddy Kong
K. Rool
Samus/Zamus
Ridley
Link
Zelda + Sheik
Ganondorf
Toon Link/ Mask Link/ Young Link
Tingle
Pikachu
Jigglypuff
Pokemon Trainer (Squirtle/Ivysaur/Charizard)
Lucario
Zoroark
Pit
Medusa
Kirby
Meta Knight
Dedede
Fox
Falco
Wolf
Falcon
Goroh
Marth
Ike
Gharnef/Black Knight
Ness
Lucas
G&W
ROB
Ice Climbers
Balloon Fighter
Sukapon
Olimar
Little Mac
Isaac
Saki
Starfy
Snake
Sonic
Megaman
---------------
That's about 51 characters, not counting transformations, extras. I feel like that's kinda generous, but I honestly don't see them cutting that many characters, if any. Adding characters is always a better option for a game like this. And 15-16 more isn't too many.
Thoughts? I know alot of this, or any of it, isn't new stuff. Or ideas, but I thought I'd put my real thoughts out there. Cheers!