Fandango wasnt a failure at all IMO, the position he was given was. He was legit doing the "ITS FAN-DAN-GOOOO" shit for a solid 5+ months AFTER WM. Jericho gave him a huge rub, and IMO he was great in the MITB match.
Adam Rose could succeed, but with the NXT and how shit smackdown/main event/superstars are to the ACTUAL product, main eventers are midcarding or midcarders are future main eventers at this point in time. When Shield breaks up, you are talking 3 (eta) matches per RAW being split up that are now taken up in one. There is no future for ALL these stars, you either succeed or you flounder, and it isn't 100% even on the star.
Look at Ryback, his anti goldberg heel shit could have been great, but his booking has been unbearably horrible. Is he great talent? No he isn't amazing, but Swagger has more credibility and that dude cant talk right.