I'm far more interested in the Source than the shards, so for me it would be Meracydia and Ilsabard that would be top of the list.

If we do go to a shard, I really hope it can be its own place with its own unique cultures rather than being particularly associated with one FF game, like they did with the Void/IV and with Dawntrail.

I'd personally like the Scions to stay with us, but in groups of 2-3 at most per expansion and to rotate out as needed.