I have to say I really like how my suggestion turned out, even if you did not. Looking below the town of Pashvie, the blur created a nice "pass" type effect in the new copy while that area looked kind of odd in the original technique.
Also, I LOVE the mountain lake idea (and am trying to do something like that on my current map) but I can see how using my blur messed that up a bit. I am sure there is a way to fix that area a bit while keeping the rest of the blur area intact. I have been playing (though not perfected) creating multiple channels from the same selection and making each selection a bit different in size by changing the threshold and using a bit different blur for each. I am far from being artistically inclined, but I am just playing around with some ideas and trying to learn how GIMP works. The only problem with the approach of having multple maskes is that ones you merge mask and go past your undo buffer size, you can't get rid of it, so I have been playing with saving the file under multiple names to allow me to go back if needed.
Oh, and if you feel like playing with it, you could also try doing the same bluring thing on the dirt layer to make the dirt->grass transision a bit more naturual looking. Again, not sure how it would work (I have not gotten my latest map to have the dirt layer look good yet so skipped ahead) but give it a try if you like.
Over all, very nice map. The rivers look a bit blocky, but that might just be an artifact of saving to this format or the original map may not have been big enough. My only real complaint is that the city icons don't really match the map style. They are very pretty, but I would probably use overhead type views of the towns in some way as you have for the rest of the map. Not a big deal, just something to think about.