#2 Character development
Those two words are integral to any successful star in wrestling, which is why it boggles my mind that WWE has yet to apply that formula to the Cruiserweights. The only thing we know about the Cruiserweights is that they're excellent wrestlers and not much else.
Sure, a case can be made that the Cruiserweights in WCW way back when, didn't have characters, but that was at a time when the world hadn't been exposed to the wrestling they were bringing to the table. Now, wrestling fans have virtually seen it all, so they need a reason to get behind today's crop of Cruiserweights.
The closest thing we have to a Cruiserweight with character development is The Brian Kendrick, who was fired from WWE years ago and has since returned to take the title. But what about everyone else? They have their own stories; WWE just needs to be willing to tell them.