Update:
This is another (and slightly changed) version of the map which will be presented to players.
I tried to give it a more hand-drawn like look, so I traced the original islands in Illustrator and put them back into PS. I also reduced the number of highlighted buildings- this version only shows public buildings. It is supposed to be a real map given to strangers in the town, drawn by hand onto some old paper that happened to be at hand (a palimpsest, so to say), hence the parts of scripture still visible.
Still this is only another experiment, if you have a brillant idea how to improve the picture then please let me know