These are looking good so far Coriolis. As I've said, I think the biggest area where there is room for improvement is in the mountains, particularly in "Part 1" and "Part 2". You may wish to check out the tutorials section, there are quite a few different techniques for generating mountains in GIMP that can help you out here. I have a mountain creation technique in my Eriond tutorial that I think would work well with these maps but it may be a bit advanced for someone just starting out. However, if you go to the last page (or second to last page, not sure) of the Eriond tutorial thread, Waldronate has offered an alternate mountain creation technique that is much easier and would look quite nice with your maps. It requires getting one more program however, Wilbur. The program is free and Waldronate has created several tutorials that will walk you through the process of how to use it. It is up to you if you wish to go this route of course, there are other good mountain creation techniques as well.