This is book 3 of the Imperial Radch trilogy As such, given how much I enjoyed the last two, and was engaged with the universe Leckie created, I continued with this one (and, let's be real, the next one, too).
Much as the previous two, this book has a society commentary aspect wrapped inside the science-fiction part of the world. In particular, this commentary is about power, the use of power, the corrupting influences of power, and the collateral damage of power. Standing up to power, saying the right thing, doing the right thing, it puts one at a complete disadvantage. One needs to have an entire acceptance of one's small part of this universe, to have acceptance of the meaninglessness of everything, and to have acceptance that, well, this is going to hurt, this standing up for one's ideals.
It's an ugly, nasty mess. Most people lose.
Some don't.
Some become the monsters they fight.
I vaguely recall that Susan and Rob didn't like this book as much as the first. If this is the case, and I am not sure it is the case, I would guess the lack of world building is part of the reduced excitement compared to the first book. This book starts two weeks after the last book ended, so the first book is needed to understand what is happening in this book.
This book doesn't nicely wrap up everything in the book, but it does wrap up some parts of the origins and destinations of some characters. The universe created is definitely one that can linger for a good one or two dozen books.
I personally enjoyed this book, both for the science-fiction part and the power play part. Again, recommended.