Even though not all questions are answered, I still feel satisfied with this book.
With this book, I was more at ease with the underlying technology of this universe. Having a technology fail is a good way of explaining it. And the author does do a good job of making a hard sci-fi novel readable and enjoyable.
By the third book, the author is more comfortable with the character of Cherwin and allows her to fail.This overcomes the problem I had with the second book.
The climax of the book flowed naturally from the characters of Jedao, Cherwin, Hermiola, and Kujen. I believe Jedao's mistake contributed to the plan's success because it lulled Kujen into a false sense of security.
With compelling worldbuilding and layered plans, Machineries of Empire is a brainiac trilogy exploring ethics, cultural hegemony, personal agency vs loyalty, immortality, and intrigue. Revenant Gun is a flawed conclusion of this series, but it still manages to deliver compelling resolutions.