A world revamp will very likely revamp Kalimdor & Eastern Kingdoms *for level 60-70*
Redoing the level experience in Cata took development time away from levelcap content & is something they would want to avoid, especially now after finally getting the leveling system to something they wanted in 9.0 so they wouldn't just revamp that *again*
So they might settle in new places but they're not going to design new starting hubs.
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That the naaru also fought the legion & the way some of them talk about nature worship leading to corruption reminds us that the Light & Void are not particularly at war as much as they are at war with *all* the other forces.
In fact I'm calling it, the next villains will be Turalyon & Alleria doing a tyranny of the light storyline but it's them ushering in an alliance of light & void against all of creation