There is really nothing in this book that I can think of to complain about, actually. It's short, so it's a quick read that doesn't drag at all; it's just full of Steven Brust's signature humor and action, the characters were as good as I could have hoped, and the plot, while it wasn't hugely original, was just perfect for what this book needed. The flashback scenes and the beginning-of-chapter witchcraft scenes were an interesting way to fill in the main character's history and to add pages to the book--even though most of the details were already laid out in Jhereg, I didn't mind rereading them. They fitted nicely and didn't interrupt the main plot at all; I think they were more like a quick break, here and there.
This series is shaping up to be a new favorite. I can't wait to read more.