Give us a better view (zoom in on the picture), because I can say hardly anything about this one. From what I see, I do not like the ground (the grey road ground) and the water around the castle looks a bit dodgy (I think using the standard water would be more efficient and give a better effect).
Other than that? The castle is kind of small and there can be not many details, but that's what I will only be able to confirm if I see the larger image. What is good about your map is that you are not affraid to use different grounds for different things, ie. the roofs and there are some darker grass patches. I really like that.
There is one thing that would make the castle/city look a bit more realistic - you can separate the place into two regions: rich and poor (ie. the castle and the houses), by using different terrains for the road: dirt and pavement.
Overall? I can't say much about the picture, but I'd give it 6/10
Regards
Sey~