Oh my goodness, this is beautiful! I am in love with the idea of this map! Maybe add some white highlights to the water to give it some more shine? Only thing that bugs me as well is that the border around the stars look a bit pixel-y (couldn't think of a better word than pixel-y...) to me. I think the rest of the map overall has fairly smooth lines, it's just the stars that seem a bit jagged. But that's just me nitpicking as it's not something you notice unless you look at the map in full size.

Aside from that, I think everything is fine. I really love how you've drawn the cliffs and the jagged lines. The colours are all lovely as well, especially the sky. The purple works really well with all that water.