#4 Cesaro
Much like Rusev, Cesaro has seen his WWE career slowly fizzle out after initially showing promise following his promotion to the main roster five years ago. In his case, however, there are noticeably fewer signs that any of this is about to change.
Mostly, this is because he's still stuck in a tag team alongside Sheamus. That's not a bad spot in and of itself, of course, but it's a long way from the top of the card, particularly given WWE's unfortunate habit of allowing once-great stables to fall into irrelevance soon after their push.
On the plus side, another thing that Cesaro shares in common with his Bulgarian counterpart is that he also remains pretty popular with the audience. That doesn't always mean you're going to the headline the show, but as Rey Mysterio showed, it can take you a long way.