Wouldn't be worth it, especially if your suggesting the lore stay the same.
If you suggested they created a entire replacement for WoW going forward, such as a new "Vanilla", a entirely separate game client that allowed us to copy over our accounts and everything there within, then yes.
However I don't think blizzard has the capacity to build such a large, successful game anymore.
Creating Warcraft 4 or starting a new title that could eventually end up as a MMO would be preferable.
Seeing the way WoD has turned out, there isent much to do outside of raiding and pvping, garrisons have turned the game into a log in, send followers on missions, log out, kind of game, which is similar to cellphone games.