Jakyl, you're not a Heel just because people boo you. Not in the modern Wrestling World. You are not a heel when I boo you as a person but when I boo you as a character. I never booed Rock as a person it was always his character. 
When Cena turns Heel, he needs to do it in the most intense way possible. No subtlety. I want Bash at the Beach. I want a gigantic moment that doesn't give people a chance to think about what's happening and simply forces them to react. The WWE has the chance to turn John Cena into the biggest heel since Hogan in 96 and Cena is capable of doing it. Wanna know how I know?
He's a Giant well I'm a Giant Whistle so go ahead and blow me: 
I love John Cena. I love all iterations. Whether he's being the rapping white guy, the debuting tough guy of "Ruthless Aggression", or even is current face form. In fact, I think I like his face form the most. Being the Face of the WWE means carrying a massive weight at all times, especially in the modern wrestling world where Batman has replaced Superman as our champion. Cena gives you everything in every big match.
Against HBK and Angle, he steps up his in and out ring performance. Go watch those promos. He steps his mic game up and his wrestling output skyrockets. When he's forced to fight monsters like Umaga he plays the superhero well. When he's matched against the personality void of Randy Orton he carrys the mantle and makes things more entertaining that they should be. 
I understand why people dislike him. I do. I'm just not one of them. I'm an old wrestling fan and I still appreciate a great face because they're such a rarity.
        
            
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            Realo won gold at the Sex Olympics with a BROKEN FRIGGIN NECK.-Voltch