Given the earlier works' pretty communist overtones, it is a bit weird that this one ends with the government being reformed after

Spoiler

putting down a slave revolt

. However, I think that this book succeeds at concluding the established character arcs and creating a metaphorically resonant vision of liberation, if not one that's literally taken to the societal level in text. Nathaniel, Bartimaeus, and Kitty all grow and change so much throughout this series and it's really a joy to watch their arcs unfold. Also, I think it's cool that the end actually addresses

Spoiler

the "after" of a revolution

, at least a little bit.