EDIT: This thread assumes Kara is 18 post-Revamp and Dick is 19-20.
After Flashpoint, Dick Grayson is obviously younger than he previously was and thus in the age department it is certainly possible to allow the romance to happen, since I don't think that Kara is 15 anymore [if it is I'm creating this thread for nothing]. The real part of what interests me is to see what the "next" version of the World's Finest would look like and I can definitely see that there is some possible chemistry between the two of them. Who better to show the girl who hates humans that humans can be good, than Dick Grayson, a man of flesh-and-blood as well as an optimistic and pure personality.
Never liked the pairing on New-Earth, but I wouldn't mind it now [Of course I have other preferences, but that's off-topic]