Maybe WWE feared having someone who'd done all the jail time as he had as the face of the promotion? R-Truth's pushes always falter since he can't do any Canadian shows because of his criminal past, as a title holder, it would become an issue. There are also the rumours that MVP was a pot smoker and didn't like the company stance on it. Then there is the other thought that he just isn't Main Event material.
Miz - Arquette territory, bs, the dude is fantastic, he has spent the past few years working his ass off to transform people's perceptions, the JBL's and the fans who thought he didn't have it and he's done a damn good job, to compare him to a skinny actor who showed up for a short goofy stint to promote a movie is whack!
The Piper, Steamboat, Perfect etc. never held a title argument gets tiresome. Does the belt get passed round to often at times yes. But these days more title reigns are guaranteed, they have to occur, with all the increased tv and ppv, its a different set up to back in the day, stories are processed and a much faster rate, those guys were in their prime during 3-4 PPVs a year periods, things were stretched out, you had merely one World Champ, put simply, those 3, these days, with their talents would have reigns, well maybe not Steamboat, I bet they'd say he was too boring, but you get my point.