I have one word for you: Cataclysm.
How you will continue the story? You realize that anywhere between 7 to 10 years have passed in Azeroth since the beginning of WoW and Cataclysm?
Even outside of having some another world warping event like Cataclysm, "Redridge Rambo" happened 7 years ago in story. That's almost half a generation there. Your Rambo has long since moved on, alongside with his comrades and enemies. But the citizens of Redridge who gave you quests all these years - they are all still there. What quests they would give after all these years? Maybe nothing and it's all sunny skies no cloud in sight, but maybe something actually did happen - given in 10 years of Azeroth time that is WoW story you had frikken' half a dozen world ending, often galactic level threats come and go.
Same goes for other areas. They are stuck in limbo not because there is no story to tell, but simply because WoW is huge and Blizz can't sit there day and night updating old zones all the time.