With how popular MoP Remix was, it's a safe bet it will be brought back to lead into Midnight.
Which expansion do you think will be the focus this time? Will it be WoD, which follows MoP? Or will it be a different expansion?
If they want to go with another expansion that has little to no quests that send you to other places, TBC or WotLK could work. So could Shadowlands. If they don't care about that, Cataclysm wouldn't be a bad option. You'd be able to quest across two MASSIVE continents. Legion is largely on the Broken Isles but some quests and Class Halls have you in other places.
What about features you'd like to see done differently in WoW Remix this time? I'd like to have the option of converting chars from MoP Remix before the event ends. I'd also like the option of converting alts to WoW Remix this time. More so for those of us who already have a lot of alts. I'd like to see the gold and Rep Token gains drastically increased. That would allow those still trying to unlock certain things like Warband Bank slots to more easily do so.
On a related note and finally, I'd like to have a transfer system for migrating gold and rep tokens during WoW Remix to other chars. More so if WoW Remix chars are locked to it until the event ends again. We should at least be given that option.
...That's just me though. How about you?