I know this enters in the realm of wild speculation and wishthinking. But I would love to eventually see a series of open world games in different regions in different times. Perhaps 16th,17th and 18th century ships. I would love to use an old Spanish Galleon or a late Carrack in a game though of course it would be totally outclassed by later ships. Of course let's get the 18th century fleshed out first.