The whole thing is great except for the lines on the mountains. Those are, pardon me for saying this, incredibly ugly. I suggest you spend a little more time with them in maybe a softer color (Brown?) trying to make them look a lot less sloppy.
Also, the same goes for the roads, try using vectors for those, they'll end up looking pretty nice if you do.
I love everything else, Especially the use of brushes on the grass.