I like the idea of more open world games, would still like the dungeons to be a bit stronger, though totk was an improvement. I think a return of the great sea is a natural extension and could give an opportunity for different powers that would be more helpful on the open ocean, kind of like how ascend was a natural complement of caves and the depths. I think keeping autobuild and ultrahand and extending it further to boats or maybe even airships in the endgame would be really neat. Could also see them building on time powers even more. Maybe a return to termina?