Exterior is a little bland, could use some columns going up along the sides, maybe some balconies. Also try adding some different colors to the floors and walls, most of it being white isn't that great. Floors could also use some plate-made rugs. One of your pics show that you did that but it doesn't cover the entire floor so it looks a little weird. Although I really like some of the imagination put into this. The dome is a neat touch, good job on that. I used to build exactly like this, large uniform walls with rooms with little decor. Start trying to pay closer attention to detail. Add some paintings if you have room. Add small accents to the walls, variations of color for example. Perhaps some less square furniture. All in all this build looks like you put some good effort into it, but if you were to improve your building style with the aforementioned guidelines and add some more detail it would look much better.
