Alberto Del Rio would be the easiest and safest choice. Despite the WM loss to Edge, it's pretty obvious his title win over Edge is looming. Edge's last reign as been forgetful at best and ADR has been given a solid push. There's nowhere for ADR to go but up at this point.
As far second most likely...it has to be Barrett. I want to go with Ziggler but A.) He's on Raw and Miz is still getting uber-pushed and you have CM Punk as the other top heel. and B.) Despite Ziggler's title "reign" i'm not sure the WWE has complete faith in him yet.
Despite The Corre getting buried, all you have to do is break up the faction, and but Barret right back on his own and his credability is back in no time. BUT...you already have ADR on SD...Either there's going to be a multiple face turns or the draft is going to mix things up, becuase both shows have to many heel with no viable faces. Barret has a looked more suited for the ME and he's a better talker. Ironically, evem though Ziggler is officially already a world champion, if would be alot easirer to push Barret at this point. Also, it's pretty funny they were both horribly used at WM.
I want to say either Morrison or Christian get a WT reign this year but...I just don't see it. Christian just isn't going to. His best shot was last year when everybody and their brother had a injury. I suppose the window is shut yet...but with so many younger stars on the rise, it just looks like it's too late for Christian.
Morrison might just have to get pushed just for the sake of it. Raw already has Cena/Orton but they're both kinds just...there. Raw needs another face at this point and Morrison is the only canidate by default. Still, l i'm pretty sure Cena or Orton would get another for Morrison. From his spotty mover-set to his lame gimmick, to his underwhelming mic-skills, it would take alot of work to make Morrison seem the least bit credible. Especially on Raw. The guy just isn't ready to carry Raw as top face...and more and more it lookes like he never will be.
As far as Kofi goes...
Lasty there are two dark horse. First Cody Rhodes. I knows, he's only 25 but he's done more wiith what he's been given than anyone in recent memory( that means you JoMo). It's hard to believe this is the same Cody with the terrible lisp who was only know for not wearing knee-pads and being Orton's glorified lacky. He's made all the people who proclaimed Ted the crown jewel of Legacy look like an idiot, he's been having consitently solid matches...looking quite comforable against proven main eveners, he's been delivering golden promos(he carried the feud with Rey singlehandily), not to mention he didn't just strike gold an average gimmick that could stunted the carrers for a lesser superstar...he managed to evolve it. Compare his Dashing promos where he instrusts you how to spit to his recent promos, where he manages to capture all the little mannerism nuisances of a broken mand. The guy has grown more in one year than the rest of the roster combined. If ADR doesn't take the title from Edge, I wouldn't be shocked if Rhodes was at least in WT contention.
The second would be Drew McIntyre. There's no real viable, concrete reasons... besides the fact he has the look, and a certain untapped prescene. His theme, as well as the manner in which he carried himself right before creative gave up on him for the time being. In the EC hewould've looked totally believeble had he emerged the victor. And I know he's 24 but I have to at least consider him because it would be to eady to build him back up, and even have him win a WT. He already has the finsiher, he was completely believebale as the serious badfass, he already wrestles in a way that would allow him to have a good match with nearly everyone (good, not great), meaning he's not like say JoMo who is too spotty for the ME.
Perosnally, I don't see many of the guys as true main eventers, but it was based on who is most likely. Christian is over the hill, ADR is overrated, barret is meh, Ziggler is just...missing something, and Morrison is Christian all over again. Drew has ALOT of untapped potential but he's not ready. Cody is the only one at this juncture that I could see as a guy who would fit in at the top, but not just flounder out later(ala Swagger, Sheamus)...seriously, if he continues to be half as impressive as he was last year, then he has to win the SD MITB.