I never really like the Cruiserweight Championship, but merely because WWE never made it seem important and they would always have 6 man challenges and never any real rivalries. I really didn't even notice them take the title away until somebody said something about it.
The UFC is basically a bunch of jobbers compared to Cena. He beat brock, won matches after getting DDT on concrete, comes back from a life threatening injury in like 2 months, etc. No MMA fighter is as legit as Cena.
Historically, I believe the Cruiserweight Title's weight limit was 225 lbs. Most of the roster are cruiserweights.
Ted DiBiase, Jr (although he's not a high flyer)
Primo & Epico
Zack Ryder (although he isn't much of a high flyer or technical grappler)
Some of them, despite technically being cruiserweights, would probably not even compete in the cruiserweight division, because they've already risen pretty high up the card: