I'll start off with the bad things: I wasn't crazy about the way the book was written, mostly it was fine but the occasional badly written line or the use of longwinded posh sounded sentances for the sake of it started to irk me. Also the use of "Great seas!" and "What in the Middluns!" also started to grate on me, I appreciate the use of exclamations exclusive to the book and the regions created, but still, I don't want to see it in every conversation. 
 I actually adored the main character, Katsa, (i noticed her flaws more the second time reading it) her strength and independance was admirable. I also understood her anger, she is portrayed as an agressive girl who can't control her temper, as a product of the "Grace" she has and her upbringing and the way she's been treated. I liked the depth to the character it gave her and also gave brilliant opportunities for character development. Po, was also a character I greatly admired and he has a very interesting personality and past which compliments Katsa's. 
 The concept of powers called "grace" was also a lovely idea and I liked the link between them and eye colour. The book created a beautiful world, similar in my opinion to the world of Eragon which I also liked. Towards the end I have to admit the plot got a little bit sloppy and confusing but I'll overlook that because I got suckered into it after the 3rd chapter.