I don't really like any of these ideas. John Cena becoming a GM is arguably the worst of the bunch. Why in the world would they make him a GM when he still has plenty of time left in his in-ring career? Yes they have had GM's such as Regal who can still work a match, but the role of the GM should be an authority figure not a wrestler. Cena can still work full-time so he needs to be in the ring not making matches. He could become a GM or announcer many years down the line, but not anytime soon. To do so now would be rather pointless.
Cena becoming a coach or a manager isn't much better of an idea. This is something he could do for an angle or two, but then he should return to in-ring action. Much like my argument against him becoming GM, John Cena still has time left to compete in the ring full-time and with him being one of the best known wrestlers in the world he should be used in an in-ring capacity. I have nothing against him working with other guys to help them improve and highly recommend that. I just don't think he should be in that position as a primary role. He needs to remain an in-ring competitor above all else. A mentor can be his secondary role now that he has been there for a little over 10 years.
The "Try and beat Cena challenge" idea is the best of the three. That could really help boost some guys struggling to get over if they used it right. It's something that could grow old if they do it too often though. Personally, if all the threadstarter wanted was for Cena to not be involved in the WWE Championship or World Heavyweight Championship picture for a while, then just place him in high profile feuds where he can put others over. He's done that before and there's no reason why they cannot just do that again for a while. Cena is above the titles at this point. He closed PPV's against Kane, Big Show, and Johnny this year in non-title matches. What I would do is run more mentor type angles where he could help faces get over, and then perhaps something like the "Try and beat Cena challenge" for heels that may need help getting over. He'll need to return to the world title scene eventually though. Making him into a coach or a GM are ideas I'd be against until he is unable to work full time in the ring. As popular as he is, WWE have to use him in an in-ring capacity while they still can.
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