How is Cena putting Eve over? Her heel turn is basically because they don't have the balls to turn him heel, or have him change character much so she's just something else to distract the audience to forget about that horrible feud with Kane.
Cena didn't start pushing Ryder until people were complaining about him never putting anyone over. His first tweet about him was in response to putting guys over, so it's not like he was being the locker room warrior that he claims he is.
With Punk it wasn't a Cena thing. Punk cut that awesome promo and that pushed him like crazy. Sure Cena lost to him, but that's not like Cena was pushing for Punk from the get go. With Miz he didn't even beat Cena clean because the Rock interfered in the match and cost him the win. Miz is a whole different story because he's been booked poorly.
I'm not saying that Cena is Hulk Hogan or Triple H were he buries guys, but he hasn't been putting guys over to talk about fighting for the locker room. Jericho puts guys over clean all the time. The Undertaker used to do the same thing. Cena doesn't seem like the type that actively keeps guys down, but he hasn't said a damn thing about his clean streak of blowing through guys and never selling anything. It's not like Vince wouldn't listen to him anyway. He's the top guy in the whole damn company, so he can't play the card of being there for the guys when he hasn't used his influence to get anyone over besides himself.