I think Cena would have probably have become a Main Event Heel who could run with it till a chasing Rock/Austin beat him, the only think I could see against him was if his ring work would hold him back
If Rock or Austin's "ring work" didn't hold them back, then Cena sure as hell would've never had a problem from an in ring standpoint either. Besides "ring work" does not make a great match. The match of the year in WWE so far this year is probably the End of an Era Hell in a Cell match at Wrestlemania, and that sure as hell was not a technical masterpiece.
What year "ring work" become such a big deal among smarks? Because that has never mattered in the WWE. The "WWE style" (if anyone actually gets what I mean when I say that) is based on theatrics. Most main event matches, especially on pay per view is all about Intro, Body, and Conclusion. It's all about "moments" within a match, a hard bump here, a false finish here. It may seem like other companies do that, but they don't. Most companies have nothing more than mindless matches with "Holy shit" moments that WWE is smart enough to use sparingly.
Hell Vince said it best in The Rise and Fall of ECW DVD, when he brought up how most of the matches were pretty much a visual of "let me show you guys how many buckets of blood I can draw", or "look at how many submission holds and suplexes I can do" in the case of guys like Tazz, Malenko, Guerrero etc... That's not exactly what Vince said, but that was the point he was making.
Cena does not need "to increase his work rate, add to the five moves of doom, or let his heel persona shine through" to prove how good he is.