It's a very nice building LSD, but I have to agree that it looks more like one of those English Manor houses with the affectations of a castle than a defendable outpost or keep. Most castle turrets or keeps that I have seen do not have windows on the first story(windows are just another open door once they are broken) and the windows they do have are usually tall and narrow because they are easier to shoot arrows out of and not be hit by same. That said, I really like the the way you've textured this.