I think that in 5 years Roman Reigns, Richie Steamboat, Bo Dallas, Seth Rollins, Dean Ambrose and Bray Wyatt will be playing a big role in the WWE scene. Not one of them has yet to reach 30.
Now I can't imagine Ryback replacing Cena, even if Vince does. Doesn't appear to have the promos skills and I'm not sure he could work regular **** matches on PPV. With the machine behind him he could become another Warrior or Goldberg or Batista...
All those years of Triple H, HBK, and Taker not putting anyone over are coming back to bite them. Sheamus as a top guy is laughable, but sadly he may be the best option. I think at this point they may as well give Jeff Hardy another shot. It's pathetic how far the scouting and developmental system has fallen since 2002.
It says a lot when self made indy guys like Punk and Byran are getting over better than the WWE trained robots.
I find it hard to buy that A-Ry could be the next big thing. The guy has spent at least the last year being a dedicated jobber who rarely if ever appears on the big 2 shows. It would be nearly impossible to rebuild someone in the eyes of the fans after such a long period of irrelavance. Sure most of the top guys in the past started in not-so-impressive roles but non were a designated jobber and all were given ample TV time.
As for who will be the next no.1 guy, I have no idea. There is talent on the roster and in developmental, but it's hard to gauge the future right now. In 2000, I though Jericho would be a permanent main-eventer; in 2003, I though Brock would be the top guy for the next 10 years; and in 2010, I thought WWE would never be stupid enough to make ADR and Sheamus permanent main-eventers. You can never guess who WWE will be pushing or not pushing.