As someone going into the game industry I can tell you the problem with that is: "Who the hell is Cecil?"
Look at Sonic & Snake. Sonic is the 2nd most known video game character of all and if you own a home console, you've probably seen Snake around and at least know something about him.
Obscure characters like Cecil who appear in one game of a giant series with a new protagonist in each game has absolutely no shot of being in Smash. There may be a bunch of remakes of his game, but it's still just one game.
Sora is the only character Square has that has that universal appeal that Snake has cause he's in the exact same boat as Snake; if you own a recent game console, you probably know who he is. But even he faces competition from Moogle & White Mage who have guest-starred in
TWO MARIO games. But they suffer from what I call "Store-front Mediocrity." If you remember the box art for Brawl, on the back, taking up a huge chunk of it was "
Solid Snake & Sonic the Hedgehog join the Brawl!" "Moogle joins the Brawl" doesn't sound as appealing as "Sora joins the Brawl!" or "Ryu joins the Brawl!" or "Rayman joins the Brawl!" That's what they're really looking for. They're not handing out character slots for Geno. They're not handing out character slots for Ty the Tasmanian Tiger. They're looking for big names. For every 3rd Party developer they partner with, Sakurai has to pay them to use their character. They want characters that will make people buy the game JUST for that character.
It's just smart money. Like take this for example:
When Sega got the rights to make games for the Olympics, they thought "Hmmm. A good Olympics came might sell well...but if we make it Sonic & the Olympics, that would sell a whole lot better." Then came "But wait! What if we get Nintendo in on this and make it Mario & Sonic at the Olympics?! That would sell EXTREMELY well!"
Companies have to bite the bullet and siphon-off some of their income to others, hoping that with those big names combined, fans of each series will want to own those games. The name has to be big enough to make a profit off the deal, which is the main problem.
That's why Smash 4 will have 4 3rd Party character slots at the very most. It would just be bad business to have 4 out-side publishers siphoning off your money with only 2 or 3 of them actually helping the income. Unless the extra characters are from existing deals like Tails or Raiden, Sakurai would be stupid to add 3rd party characters just to appease Smash fans with a bigger 3rd party roster.
And speaking of the 3rd Party roster, using the logic I stated earlier, I can tell you a couple 3rd party characters almost guaranteed to be playable in Smash 4.
Sonic - Absolute shoe-in for Smash 4. Gaming's second banana. Second only to the king himself; Mario. (If you exclude Pikachu) It is an absolute no-brainer. He'll have a spot in the game's programming before they even finish the Nintendo roster. He brings in cash just like slapping the Mario or Pokemon brand on something. Guaranteed. Money. Guaranteed in the game. No sweat off Sega's back. No sweat off Nintendo's. Profit all-around.
Ryu - Again, an absolute shoe-in. If they add ANY other 3rd party character is has to be Ryu. When you think fighting games, you think Street Fighter first. Ryu is a big name which comes packaged with big bucks. In fact, he's arguably gaming's number 4 guy right behind Mario, Sonic, & Pikachu. Capcom has no reason not to lend them Ryu for Smash 4. It's free money for Capcom. Absolutely free money. All they have to do is check on the project and make sure Sakurai doesn't tarnish Ryu's good name by making him goofy or out-of-character. The ONLY way that Ryu wouldn't be added into Smash 4 is if Smash 4 directly interferes with the sales figures of a big Capcom game coming out just after Smash 4. But even then they should make that money back and more off Smash 4 so, again, no skin off Capcom's back. No skin off Nintendo's back. Profit all-around.
*Regarding Mega Man: Mega Man's a big name, it has to be said. But Mega Man isn't Capcom's show-pony anymore. Ryu is their mascot. Their Mario. Their time-less character that hasn't really changed since he became popular. Mega Man's appearance has constantly changed to the point that he's almost entirely unrecognizable as Mega Man. The most recent games being the best example of that: http://images.wikia.com/nintendo/en/images/1/11/Mega_Man_Star_Force_Dragon.jpg If Capcom gives Sakurai some sort of package deal and gives him both Ryu & Mega Man, that's fantastic, but Ryu is the bigger character & the bigger money-maker.*
Snake - Stepping away from finance for a minute, Snake pretty much leaves as an old man to go die in peace at the end of Metal Gear Solid 4. The question is; does Konami treat Snake like Ganondorf in Brawl and bring him back for "one last mission", do they move on to a new property, or do they pull-out of Smash all-together. The 3rd option is unlikely, but not out of the question. Snake is one of those decently famous characters. In the same league as Rayman or Bomberman. (Who is actually owned by Konami as they bought Hudson Soft.) While his games are of much better quality than their's, it's Snake himself is the big deciding factor. Would Snake make a profit for Nintendo and if not Snake, then who? Keep in mind if Nintendo makes a dollar more than they gambled originally, adding Snake would be considered a success. It's a complete judgment call on price vs profit for Nintendo & Sakurai's people. Konami has nothing to lose from the transaction at all, but it does however risk Nintendo & Sakurai's money.
Sora - ...*sighs* Square Enix, I am so disappointed. Final Fantasy's recurring characters are Moogles and Dragon Quest's recurring characters are Slimes with little else in-between. Sora is the only character of any merit that constantly returns in his own series. While, yes, he will sell copies of Brawl, I don't honestly expect him to even be consider because, whoops, he's partly owned by Disney. (the money Devil) Sad for you, Square. Sad for you.
But there you have it. Those 3 are just about the only 3rd Party deals worth taking aside from
maybe Ubisoft with Rayman. Sonic & Ryu are free money and Snake is iffy. If Sega, Capcom, or Konami wants to throw an extra character like Tails, Mega Man, or Bomberman, respectively, at Sakurai and he bites, that's fantastic! More characters for us! But that's the only way I'd see more than 3 3rd party characters in Smash 4.
Sorry to crush your 3rd Party dreams, guys, but that's just how the gaming industry works. Money. Money. Money.
http://www.youtube.com/watch?v=JoYWdHe4tQ4
