I would like to see BFA become a “gamestate” rather than an expansion that we simply leave behind and forget about. Moving forward, this could build upon the current warzones system and open up the entire (eventually, at least) game to endgame gameplay and progression. Similar to the way in which the warzone zones are instanced for max-level players, the entire continents of Kalimdor and Eastern Kingdoms would be opened to ongoing gameplay (with graphics updates ideally). The world quest system (themed around the competition between factions for resources and land acquisition) could be deployed throughout these regions. This could be tied to a “recruiter” in the capital cities through whom players are able to toggle their “gamestate” and access the BFA system.
This would propel max-level characters back into the world in meaningful ways, maintain a sense of faction-based gameplay (even as they are simultaneously dealing with the meta-threat of the current expansion), and utilize the brilliant instancing “gamestate” mechanics that work so well in warzones!
It could be tied to both endgame and the lower leveling process, with players of different levels having the ability to access the system at different scales, but I imagine that this is a more difficult development task.
I love world quests and the “idea” of warzones, but I feel like a system like the one I have suggested would integrate them and revitalize the base game in radical ways if it were an alternative to the typical leveling process (and provide more endgame content that is trans-expansion in scale).