I think the mountains you have there work well with the rest of the map. If anything I think the 'busyness' helps them compete for attention.
As far as the colors to show national boundaries I like what you have. Take the color for your country and make a border to go around the colored areas that is a bit darker and see how it looks maybe.
I'm not a big fan of the drop shadow though. Makes your map look likes its floating over your paper rather than drawn on it.