Honestly I don't see a water theme going on anymore. I think the games will lead more to frozen lands than water anyway. Plus two years later, maybe Unova became more relaxing and a great place to chill/take a vacation at as opposed to the storyline being based around water. Maybe there will be more to do at sea, but honestly based on the protagonists all I can think of is summer and the beach and this is how Unova's region formed out to be like. Which many people would like, no doubt. Needs moar cityyyyy though.