Evan Bourne has all the talent in the world, but even if he isn't out the door, he'll never be more than a spot-monkey. I've never been his biggest fan, but he does have a lot of talent (thanks to his background in the independent circuit) and can put on five-star matches with guys like CM Punk and Chris Jericho. But, Rey Mysterio is one of the few exceptions to the rule that Cruiserweights should not go over heavyweights. That's just WWE's philosophy. CM Punk is the hottest thing going right now (for good reason) but that's because he can not only outwrestle just about anyone (including Dolph Ziggler) but he can also step up his game with bigger opponents (like Kane) and hit the GTS on three-hundred plus pound guys.
Plus, Evan Bourne knew the rules. At this point, he doesn't really deserve t.v. time. There are countless other talented people who salivate at the chance to be onscreen on Raw and wouldn't violate any policy.