I feel like I just read 400 pages waiting for the story to start, and then it ended. Not that it wasn't a good book, but it just felt kind of... Ancillary.
Edit: I've come back to this review after a month to reiterate that I really felt like this failed to launch. I love the Expanse series like you wouldn't believe, but this really felt like it was missing the overarching plot and could have just been a short story in between novels. Maybe I'm being unfair, but that's how I feel about it.