I like it. I think it's a great sprawling wilderness map. I don't know about over-detailed. I think the only way a map can be over-detailed is if there are so many objects that it restricts the players movement and makes it difficult to navigate through. The hills on the sides are very pretty, but I hope there is more use for them then just decorative. It could be a great chase scene with characters scrambling up the hills and jumping down to get away from whatever, or there could be some goals at the top of the hills that the player has to explore around to find a way up.
As for bugs: I can't see too many, although the very zoomed out view doesn't allow me to inspect the finer details. There is a discontinuity with your hills in the upper right though. One of your hills runs on top of the other. You can do this, but you have to make the top hill be 4 squares tall on the ground, and 2 squares tall when it hits the other hill.