Hi Tom, and welcome to the Guild. I really like the colour pallette you've chosen. It looks like what you are doing is overlaying colours on top of your handdrawn map, but not altering the underlying map at all - which is fine, but you might want to say, work on the mountains a bit more to give them a more shaded look rather than just remianing as upside down V s.

Must finish my tutorial on this...

Great work so far, but I guess my advice is that now you have in a raster editor (what software are you using btw?) you can go much further than colour overlays and textures.