Nice one! To improve, I can give some hints that may be help: I think you need to solve the visual chaos to create a more readable map. Maybe decrease the texture on the water areas, use a sharper shadow for the shorelines to break apart land/sea more and clean up some of the hills/trees overlapping with the shores. The eye usually moves to brighter areas when looking at a picture, so you might want to change the sea color to something darker than land or simplify it. That way the first thing the viewer will see is going to be is where the details are. Another small thing you can do is using a more stylized font for some bigger texts and centering the words when they are stacked.

Keep it up!