-City or towns in one or more of the fjords, or on the plains by the mouth of the river?
-Merfolk villages?
-Sail boats?
-Castles somewhere, maybe at the base of one of the large peaks?
-A dragon's cave?
-Renaissance chateau or Italian villa?
-Or something special (ruined temple or portal) in the great pool in the lower left third?
-Maybe some sort of Alderaan-like Sci-Fi cities by the water or on the peaks?

I'm just spitballing here, hopefully it is helpful.