I love the worldbuilding here (I'm a sucker for ice worlds since reading Left Hand of Darkness
at a formative age), but the pacing was rough. It started out slow--very slow. But the characters and setting drew me in, and I was prepared to enjoy it as a leisurely slice-of-life novel. Then the climax hit, all rushed action and rapid (and not entirely convincing) character growth. The contrast was jarring.
I enjoyed the very end--the ghosts taking their stand at last--but I think, if the primary point of the book was to show the overhaul of the social system, I would have preferred for more of the focus to be on the characters who actually grew up with (and believed in, to a lesser or greater extent) the code. Instead, everyone
whose viewpoint we get is from off-planet or someone who has already rejected the code. It made it hard to buy it when they kept saying "oh, but the code has its uses" and therefore hard to see any real tension in its eventual fall.
I was also bewildered that so much of Trey's focus in the final third was on, essentially, preserving the divine right of kings, which really didn't feel consistent with his/her value system. I would have preferred to have him/her actively considering the eventual impacts on the ghosts and other underclasses, but that seems to have been by and large a convenient side effect of the restoration.
I did enjoy the way one of the main character's genders was left forever unrevealed; it could have felt like a cheap trick, but the lack of pronouns flowed naturally and, in the end, it really didn't matter.