Dixie Kong seems most likely to me simply due to the fact that they almost put her in Brawl. Dedede was almost in earlier games and made it into Brawl, which shows that they do remember who they've considered and probably keep concepts from early development of previous games. Dixie has an excellent chance. The Donkey Kong series definitely deserves 3 representatives, and the only reason K. Rool has the most remote chance against Dixie is because he's a villain, but Dixie is a female, so I feel that counters that. Aside from Dixie, Shulk seems like he has a decent chance, as he's most representative of Xenoblade Chronicles, and since X is coming out, that boosts the series' chances of getting a rep. Saki I'd say is 3rd most likely, since he's had an assist trophy and his game is on the virtual console. Ridley, I'm sorry, but I just don't want him. There's big, and then there's TOO big. Bowser is big. He can be downsized though. Ridley is TOO big. It wouldn't look right if he were downsized. Samus fighting a Samus-sized Ridley? I don't think so. Look at how much smaller Mario is than Bowser, even in Brawl. Yet Samus is really tall. As tall as Bowser. Ridley would have to still be bigger than that, bigger than every other fighter, just to avoid having his proportions looking awkward, and then his size would still be awkward. Ridley makes more sense as a boss. Especially when you consider his attacks, which mostly involve him flying and using his tail to attack in flight. He'd end up being more of an aerial character than even Jigglypuff. He needs almost continuous flight to be effective, as well as tons of space, and that just doesn't work in Smash Bros.