Forbes posted a story claiming that WWE officials have been discussing the possibility of turning John Cena into a heel, but more seriously than in the past when it has been done.
Their report is claiming that his role within the company isn’t as strong is it once used to be when he was wrestling a full time schedule. There's a belief they may end up turning Cena heel now. WWE would then be able to utilize him more by helping the next generation of top babyfaces get over better.
It also sounds as if this would be a potential boost in ratings, as they feel the audience may tune in more because a Cena heel turn is something that tons of people a part of the WWE Universe have died for.
The idea is that Cena will return from his break, and later enter into a feud with The Undertaker at Wrestlemania 33.