I still remember all the kids in the audience crying when Cena had to join the Nexus. What people should be hoping for is a new direction for his character.
It's not even a new direction, just a couple tweaks. Just stop playing the underdog card so fucking much. Ironically, if you take his match with the Rock at face value, he can play the underdog card here. Rock's beat him already, Rock's got the title and ended the longest run in 25 years, Cena's had a mediocre last calendar year ... it actually is okay for him to play the underdog role here.
You know, if he hadn't used it every promo for the last however long he's used it. For me, if he stops that and the company moves to more TV-14 story lines and takes the reigns off him for promo's, I'd really enjoy his character far more.