World Of Warcraft: Khadgar is a shit wizard!
The way I think it would be:
Kul Tiras
Nazjatar
Kezan
Northern Plaguelands
Dragon Isles
Endgame Pvp zone: Banana Island (Tel'abim)
Endgame PvE: Zandalar, much like how in Suramar you helped the Nightborne, I'd assume you would aid Rastakhan against Zul.
Ny'alotha would probably be the Argus of the expansion, with a raid where you'd finally face N'zoth. Would be a huge zone with WQs and a story arc too.
New titled leaked World OF Warcraft: The Mist Burning Wrath Of the Legion Warlord Cataclysm
Muffinus is with us, brace yourselves