I've been using Photo Pos Pro for all my photo-editing needs. It's a free software as well, but not as powerful as Gimp. I'm still using the very old version and have not looked at the updated version of Photo Pos Pro, so don't know what improvements they made. I didn't want to have to re-learn the few things I regularly use.

The problem with North and South additional maps is that travel becomes very far away from the starting point. It is less distance to move east and west. If I expand the game again, I could then add a north and south map to make the world bigger.