The catchphrase itself is very stupid. There's no substance behind it. Its YES or NO. What does it mean? Nothing. Its just a word, and a very nondescript word at that. Doesn't relate to his character, or push a gimmick, its just...there. Therefore, I'm not a fan. I wasn't even a big fan of What either. Didn't see the point to it.
On top of that, I don't have much respect for it. Its mind numbingly easy and there's no originality or creativity in it. Anybody, literally anybody, could make it work. Fuck, look at AJ...she even leeches off of it. Not everyone can go out there and call themselves the Ayatollah of Rock and Rolla and make it work. Jericho can, which is why its unique. He can do something not everyone else can do, and the phrase itself is unique. That's why its awesome.
Are words like 'substance' really applicable for a broadened comedy role though? In WWE of all things? Methinks you're taking this call for improvement a little too
far. Get too pedantic about making humour more 'smart and upmarket' and you likely suck the fun out of it for a lot of the audience who aren't looking for that. And if do you want to get technical about Bryan's catchphrase 'Yes' and its relevance, then its origins are traced back to heel Bryan's weaseling about all throughout his WHC 'survival' reign. The 'No' thing is just a continuation of this schtick while playing it up even more for those in attendance. Just like that awful 'What' chant is.
And let's be honest, a tagline like 'Ayatollah Of Rock n' Rolla' is only cool in the context of pro wrestling. Say something like that anywhere else and you'll likely get tarred and feathered. In saying that, however, it certainly does fit the bill of the Chris Jericho-Y2j character.