I'd really like the Enclave to return as well. Surely they added a nice touch with Arcade Gannon and his little storyline in New Vegas, yet it wasn't satisfactory enough. A Fallout sequel based on the return of the Enclave and ideally Frank Horrigan (who is, as we all know a super mutant, and somehow survived) would be super awesome.
I want to see a game where Enclave have become a bit more....nicer so they can play the role of a joinable heroic faction in that Fallout game without having them be the bad guys. Maybe have the game be set in Chicago where there should be Enclave left and have you the player as a baby brought up by the Enclave and ready to assume your position as an officer sent out to expand the Enclave and with the possibility of leaving Enclave and what not.
Tired of being forced down my throat with Brotherhood of Steel propaganda crap. That's why atleast it was nice in Fallout 3 that you could put in the virus and not blow up Raven's Rock and in a way support the Enclave. Although it didn't lead to much else. But with mods you could go on to join the Enclave fully later on.
Or worst case scenario (or good depending how you look at it) a Fallout 2 remake where you can pretty much join them and support president Dick Richardson