Actually not too bad.
Characters: somewhat flat, but not completely one dimensional
Plot: different enough from Cinderella that I wasn't able to completely guess future events
Tropes poorly handled: One big trope hinted at about 100 pages in comes to cheesy fruition near the end. Saw it coming.
Length: I understand this is a trilogy, and I haven't read the other two books, but I wonder if some aimless wandering could have been cut to make three into one or two meatier books.
Objectionable material: none really. Some surgery blood.
Overall impression: don't regret that I read it. Might read the others if they magically fall in my lap