Just thought I'd share my opinions on where Smash will go next, in terms of the pre-existing playable franchises. My thoughts on Mario and Yoshi Series first.
Mario has reached a point in Smash where the Roster is, quite frankly, a bit ridiculous. There are seven individual slots, plus seven additional fully-fledged alt models...it's gonna be interesting to see how it's handled next time. I feel like around Brawl *this was before Galaxy really took off*, Mario was sort of waning...Sunshine, NSMB DS, nothing really that mind-blowing..but recently I'd say he's experienced a bit of a renaissance with a lot of solid games, which is why suddenly he's got more people in 4 compared to Brawl.
Now, first of all, I think Dr. Mario is the only cut. Why? Well, I really think he was a last minute decision here, although to be fair, he has had a lot of games recently, especially on the ESHOP. Nes Remix, Dr. Mario RX, Dr. Luigi, etc. I almost consider him an "ESHOP Rep"...in fact, if the Wii U has an Eshop Stage, I bet it'll be Doc's. But I think he might get the boot next time around...I'm interested in Sakurai saying why he brought back the Doc.
Bowser Jr. and Rosalina are the next in terms of being cut, but I don't see Sakurai dumping such an imaginative and alt-filled character like Jr. (on the other hand, perhaps the level of time it takes to make such a character might mean Sakurai will cut him next time due to time constraints, etc.). Rosalina doesn't seem like she's leaving the Mario Series soon, and in fact I can only see her getting more appearances, so yeah, she's good to stay.
Now, let's talk about up-and-coming characters...before Brawl, Rosalina was the next big thing in the Mario-verse. Right now, argurably there are two characters that are anywhere near her level in terms of being in the spotlight...
First, (Captain) Toad. There's a lot of suspicion I have right now to suppose he's gonna be DLC...that weird advert on that Japanese site, the random mention in the Toad Trophy. Now, while he can't "jump", this is easy to get around...introduce an element that spawns that propels him into the air, but otherwise works like a jump. But even though Captain Toad is new, he's basically Toad, a long-lived character, and thus has quite a lot to draw from. Wario Woods, for instance, for more puzzle-based moves, and his appearance in Mario 2 USA and 3D World.
The next one is...Nabbit. I mean, dude has had quite a few playable appearances already, including a mainline title. Although he wasn't popular enough to be in Mario Kart 8, although I think he has a chance as DLC. I don't think this'll happen, and Nabbit's popularity will be short lived, but a thief-archetype character would be interesting.
As for classic characters, Daisy and Waluigi are the most requested. Neither one of them have really had any breakout roles though, and unless that changes, well, I still don't think they'll make it. Sakurai not making a True Daisy Alt for Peach, literally the biggest "duh!" ever, seems to suggest he doesn't think much of her. And Waluigi is almost the poster-boy for Assist Trophies now. No other Classic Mario Character has really surged up recently...I guess Boom Boom came back, but he's not really...well, interesting. If tag-teams return, though, a Boom Boom/Pom Pom Team would be interesting I guess.
Finally, we've got Paper Mario. Certainly a well-requested character, and his chances are certainly looking bright now that Smash actually gave him a level. Hopefully Sticker Star didn't kill the series, though.
Moving on to the Yoshi "subseries", well, I'll be honest...I still think Yoshi should just be merged back with Mario, and even Sakurai seems to think so based on the character layout. Yoshi games tend to be not well regarded, Sakurai didn't give us a new Yoshi Stage, A.T., or "character", (actually, are the Shy Guy counted as a Yoshi or Mario enemy Trophy-wise?), and, well, I dunno, Yoshi feels sort of antiquated now being his own series. Maybe Wooly World will begin a Yoshi revolution, but regardless, there are three Yoshi characters who I think have a chance...and two of them are basically Mario characters now.
First, Baby Bowser. Yes, we've got Bowser Jr. now, so this would feel redundant (even Nintendo basically made their designs quite similar recently), but Baby would probably play as a straight up Bowser clone. But I think his chances are pretty much dead, we don't need another "Koopaling", even if he is the Yoshi Series' Boss.
Next, Kamek. While he's a generic enemy, he's also an individual, and I feel is the main antagonist of the Yoshi Series. There's a lot of potential, and he'd serve as a nice counterpart for Yoshi being an individual-named-after-species (in Japan they're all Kamek) and has lots of moves he's shown off. But then again, poor Kamek can't even get into Mario Kart. Atleast he was playable in the latest Golf and Baseball which was a start, and has had larger roles in the platformers and RPGs again, but now he's almost a main-line Mario character again. But I think he'd still fit well as a Yoshi Rep, bringing along his magic skills.
Finally, Shy Guy. There's never been the "Shy Guy", so it'd be a bit weird since we'd have a character that was a simple mook and not an individual, but they're the key enemy of the Yoshi Series, and a popular character in their own right. There are many species of Shy Guy to draw from in terms of a move-set, as well as their spin-off appearances. There's a lot of fun you could have, and I doubt anyone would be bothered just because they aren't an individual character. Only problem is, it'd be weird to use any stage that has a Shy Guy in the background, and that means a lot of old stages have to be changed. Or maybe not, since they could find a way to make the Shy Guy distinct.
I don't see Yoshi introducing any major new characters....it's not really a series that does that...but perhaps Yarn Yoshi could be its own character? I don't think I'd want two Yoshi, though.
