First (somewhat) World Map - Looking for all feedback

[jjosch]

Well, I am currently creating a new homebrew RPG campaign setting, with mostly standard D&D background. The map started out as a complete world map, but it now ended up showing only parts of it. It took me about 12 hours total, although at least half of that was trying to figure out what tool does what (which I still don't know, really). I used GIMP, a parchment texture, free-to-use brushes for map making, and thrown in a cloud render for more texture.

I know I am not really happy with it yet, but cannot even say yet what it is that bothers me. There should be hint at ice sheets / north pole at the top, the forests look to regular, especially the jungle on the southern continent/island. In addition, I realise I am not good at creating a believable world climate, I guess. Oh, and I wanted to draw mountains, forests, etc. on my own as well as paint the map in shades of green and yellow hinting at the varying fertility of lands at first, but could not, for the life of me, figure out how to do that without it looking like I had a stroke while trying.

I am happy to get any hints, tips, critique or thoughts. I know I have quite a ways to go to be able to make stuff that is even half as good as what is posted on this forum here.