Across the Nightingale Floor

I love the idea of Across the Nightingale Floor (Lian Hearn, 2003), a fantasy set in an alternative feudal Japan, complete with samurai and ninjas. I didn't quite love the characters, however--I just liked them--which kept me from being fully hooked by the story, though I finished it just to see how the plot would resolve and which of the three threads of his history the protagonist would choose to follow.