I know Ember Bay tried doing this, but the volcano area ended up becoming a central part of the map. I would love an oceanic area purely consisting of shallow islands, maybe a larger island that will play a part in the story but not nearly as big as the volcano. Southsun Cove tried but the islands are still too high, the zone is fairly small, and the main island takes up a huge chunk of the map. I also am not super fond of the pink-coral aesthetic of the map.
I'm talking like 40 tropical islands or so. Some tiny, some decently-sized. These islands have foes, a few of them might have verticality, plenty of NPCs, some renown hearts, plenty of events. It would be my dream map!