Sami's story has been the same since NXT. That's what make him a boring champion. I totally disagree about his promos as well. They have not changed. This underdog/uncertainty stuff he pulls every time he gets a push is meh at best simply because it's the only promo he knows how to give. Of course the fans are going to cheer the underdog. But now that he's champ...
Sami and Damien are very different from each other, especially considering that Damien has never really gotten over on his own. It's arguable whether he's even over now, even with JD.
So far, the Cody era has been reduced to him being duped—first by Logan in not including the U.S. Title in the match, and now by AJ during the faux retirement. This is not a great look for the new face of the company.
I think they want to use Randy as Cody's main rival. Problem is Randy is over as hell and there are no other valid heels on the Smackdown roster. The only other option is Solo, but he needs to build up some more. The top heels right now are all on Raw.