What I wish is they'd bring back previous seasonal events they aren't going to repeat. It could even be a single NPC entrance into a place with premade background areas which you can see but not enter (They already do this in cutscene areas such as the leader of Limsa's hall, any place in game that you can see the sky but not explore into. As well as the quest instance areas.) The game already re-allocates the resources needed - so right now when there isn't a lot of things going on (perhaps in 4.0 near the end) would be a good place to implement, vs at the beginning of an expansion.