Ridley
Likelihood: 25%. I feel that I am being generous with that figure, even if it seems extremely low to most people. It's by and large the western audience that is calling for Ridley's debut as a newcomer. Ridley's menacing appearance and devastating attacks will undoubtedly be taken down a few notches with the inclusion of him into the playable roster, should it happen. This would not have to change about Ridley whatsoever if he were to remain a boss as he is (twice) in Brawl. For this reason, and for the sake of consistency with the previous game, the developers are likely to have Ridley retain his "boss" status as that is his true calling. It just seems like improper type casting and a breach of justice to have Ridley play any other role. Not to mention, more work. Even if Ridley is not a playable character, he has been repping Metroid since Melee as a trophy and even more notably in Brawl as a recurring boss (just as he's been a recurring boss in the Metroid series). He needn't become playable in order to rep his franchise. This is a fact which his hype train riders seem to forget.
Want: 50%. I kinda want to see him playable. He'd probably play like a hybrid of Charizard and Metaknight. It could be done. It's just hard to see justice being done to him should he be implemented in this way.
Nominations: Lynn & Krystal.
Lynn is a big part of the glorious Fire Emblem franchise which repeatedly enjoys praise from fans around the globe. Her personality and fighting style is a no-brainer for any fighter game, but she just so happens to be one of Nintendo's golden girls. And speaking of girls, Smash Bros. needs more of them. I know I am beating a dead horse with that statement, but it is nevertheless true.
Krystal: See Lynn. It mostly applies to Krystal. Possibly Wolf could be cut for Krystal, if needs be.
A few things. Before Smash, Mewtwo was depicted as evil and down right lethal. He is seen to be overwhelmingly powerful in his movies as well as in the games like Pokemon Stadium, making him the final boss, Mewtwo VS your entire team.
In Melee Mewtwo is no such threat in ability or appearance. His overwhelming abilities are toned down to the point that many people see him as some sort of a joke. The idea that Ridley can't make it because toning down his bigger abilities or vicious look would make him "look bad" is outrageous and no amount of jargon or "scientific" speaking is going to mask the idiocy of the idea.
I mean really, by your logic the Pokemon Company should be furious that Jigglypuff and Pikachu were so much better characters than Mewtwo.
You also bring up consistency within the series, sighting Ridley being a boss as if its been some established trope since 64. If anything to keep consistent Ridley should have been flying around the back ground in the last 2 games. With each game Ridley's presence grows and its obvious that Sakurai views him important in some sense. It's 5+ years later with more Ridley support than ever before due to the weeding out of Nintendo characters and you speak as of Ridley is just unspeakably impossible to add.
You've said several times now Sakurai's team would have to do more work. Who doesn't require more work? Especially with a new move set? Sakurai's team developed Ogre, a big, nasty, bat winged monster in their Tekken games. These guys are more capable than any Smash team before and Sakurai is known to literally self destruct during development time, when aren't they doing more work?
You've been arguing Ridley so long you've found yourself reaching so far for excuses. I mean you always bring up Sakurai's famous Ridley quote, but why only the 1st of 2 sentences? Are you hoping the less informed just take your word for it. There are 2 big(very opposite) sides to that coin and you just choose to ignore one of them.
At this point its as if you are arguing because you just don't like the idea of Ridley, rather than any true technical limitation.
Chances 50%
My reasoning is purely based on the Nintendo Power quote which basically seemed like a 50/50 chance to me.
Want 100%
Nominations: Dixie Kong X 5