I actually really like this idea, at least on a conceptual level. I don't want to go to other shards while there's still parts of the planet we actually live on to explore, but it'd be really interesting to have an expansion where there isn't an actual villain, there's just problems to solve. Like, picture Shadowbringers without Vauthry (or the Tempest). I guess the problem there is making a satisfying climax for that, but it's not an impossible task.

I've actually thought of similar myself before Endwalker; that Zodiark and Hydaelyn may not have been actively altering things, but they were around that things just sorta grew around the assumption they were there, and their absence causes problems because of that. I actually was right on this one, it's the focus of EW's Fisher quests, but it's entirely possible that scales up somehow.

Yoshi-P once said that a moral choice or something of the like would be an element of 7.0, I believe, which could go along with it. Sometimes things go haywire in a way where you can't save everyone, you just have to make a choice and live with what you did.