I don't feel like I can truly rate this without having read the first book. If this was a first book of a series, I'd be a bit disappointed in the world building (super cool idea, but I have so many questions!) Maybe those questions were already dealt with in the first book though, so I can't gives this a bad rating for being a sequel that I happened to read first. 
 It was intriguing and I think I'll kept to this after I finish Ship Breaker.