[Question] A region map

In the hope of creating a fan game I decided to make a random map for a region.I know it isn't that very good but wanted to know how I can improve.
It is on the attachments.(Just so you know,i thought of making the lower left settlement some sort of battle frontier and lower right the Pokemon league.)

I find it hard to explain verbally, so I decided to show you with your map. I went ahead and changed the design of the mountains and the river, if you compare this to your original, you'll be sure to notice the changes. The following attachment is the map.



Again, the two things I changed are the mountains and the river. I changed the estuary so the colors would blend, so it would be a smoother transition. For the part that connects with the mountain, I felt it would look better if moved a bit to the left. And for the mountains, I decided to change the color and add a bit of depth to it by using a lighter color for the center. Something else that I didn't change was the color(s) of the grass/land. Personally, I would use 3 or 4 different colors, since maps tend to have 3 or 4 shades of green (in gen 3 and 4 only HGSS had a map with less than 3, but the slightly darker shades made it work). All in all, it's a pretty good map. Just work on incorporating different shades.

Hey, thanks for the advice and help.I referred the screenshot of Pokemon platinum's map while doing this.Most of the colours are from it.But I feel that you are right,i should have used more colours for shading.