I want to start by saying this book is still really interesting. I LOVE anyone who can take a sci-fi staple like subspace and make it cool. The idea that there's something more to subspace than just a place where ships can go fast between two points really shows a keen understanding of what makes science fiction special. Authors should build on the fun ideas of others. Make those things your own. The last book that I remember doing something with subspace was Animorphs, and that's a very memorable point for that series.
And I think (I hope) the series is really going somewhere with its unique take on subspace. It's for that reason I'm going to continue reading the series.
All that being said, Traitor could have used a serious developmental editing pass. Things happened in this book, mostly around military culture, that I couldn't suspend my disbelief over. I tried. I think a lot of people could probably overlook it, but as someone who actually has some military training (just ROTC, but they get really into the Military Thing) I couldn't get past it.
The most minor, nit-picky thing I wanted to bring up is the constant calling people by their full rank. For example, you're going to call a staff sergeant "Sergeant." You're going to call a major general "General." The only exception I've ever known is for a sergeant major, which I've always been told to refer to by full rank.
But the more egregious issue I've found, the thing I just couldn't get past, is the military's extreme insistence on able-bodiedness, and how this book completely discards that.
(Disclaimer: I'm not saying it's necessarily RIGHT, but that's the way it is. In combat situations, you're either in peak physical health or you're not in combat.)
So, spoiler for book 1, which I'm hoping you've read already if you're reading reviews for book 2: Rhys is brutally tortured. Tortured to the point where he cannot use his arms in any reasonable capacity. After his torture and rescue, he defects to a separate earth faction away from the empire.
There are two problems that arise from this, but the first is that Rhys is almost immediately sent into a combat situation, on purpose, to "prove his loyalty" to the centauran faction.
There's a HUGE issue with sending an incapacitated person into combat! People rely on you, and if you can't do your job, they could die. It would be one thing if Rhys lied to his superiors and said he was fine, but they were fully aware he wasn't, even attempting to augment his damaged arms with "power gloves."
The military doesn't use combat to prove loyalty. If I'm being 100% honest, it uses the natural inclination for people to follow authority and the desire to avoid humiliation and punishment to instill loyalty. Leaders emerge who understand how to control and wield that authority like a weapon--because it is. People in the military are very, VERY wrapped up in following orders. That is the entire point of it--you understand that you must follow orders, even if you personally disagree with them.
There is a way for soldiers to morally object, but because of how military culture works on a person, this isn't usually done. Humans psychologically won't do things when they think they'll be doing it by themselves. It is hard to stand up and say "no" when you're afraid your comrades won't follow you. This is instinctive, and has kept humans alive for thousands of years. It is why, in the face of committing horrible acts, people will find a reason their actions are justified rather than saying no.
(Again, disclaimer: "I was following orders" is never an excuse for atrocities. However, this is literally how the military works.)
The point is this: There are many other ways to "prove loyalty" than sending a green recruit on a combat-heavy, very important mission. War games, for example. Drills. Even games like capture the flag could have instilled a sense of camaraderie. Anyway, I couldn't get past this, and I think that might have ruined the rest of the book for me.
Instead, I would have loved to see the fallout from his disability. How Rhys learned to live essentially with severely weakened arms and how he might have found a way back into military service without necessarily having to get them fixed. There could have been so much story behind this alone, and something else the book never touched on--the psychological damage that comes from being tortured. Rhys never saw a psychiatrist, never thought about the pain and fear he went through (except when it could be used as a prop) and didn't seem to suffer anything like PTSD. Torture is a major trauma! More attention should have been paid to that alone.
This book also uses more epithets than the first, though the first was epithet-heavy as well. "The starat" and "the human" are common ones. And I'm not one to tell an author they should never use epithets. I don't find them unwelcome in most cases, until I start reading paragraphs with the same one used four times. It gets repetitive, and that's what pulls me out of the story. Moreover, it's kinda fine when you use a noun as an epithet, but there's an albino character that was relentlessly referred to as "the albino," which seemed borderline offensive.
Beyond that, the narrative suffered from a lot of wordiness. Dialogue that didn't sound natural, sentences ending in prepositions, and one weird thing this author does over and over. If a character is sitting somewhere, the narrative describes them thus:
"(character) was sat..."
Instead of "(character) sat" or "(character) was sitting." There were also a couple instances of "(character) was stood" which made me feel as if some other character had placed them there. It was just very awkward.
This book also does something that I personally dislike, and that is going back and forth between two completely different stories every other chapter. It takes me time to get into a certain narrative (IE following Rhys) and by the time it gets to the end of one of his chapters, I'm going back to what's going on with Twitch. I feel as if I am just getting into a story when it suddenly changes. I guess I don't feel like I'm sitting with a certain group of characters for a necessary length of time, and I found myself skimming to get back to the story that had already caught my interest. This back and forth has always done a disservice to cohesiveness in narrative as far as I'm concerned. If the stories were RELATED to each other in some important way, this back and forth would be acceptable. As it stands, I feel like Twitch's story should have been an entirely different book.
But even separated from this book, Twitch's story needs work, because it doesn't entirely make sense. The premise is that a character named Amy wants to send Twitch and Twitch's partner, David, to essentially infiltrate the church. The church is notably anti-starat and has been known to kill dozens of humans as collateral just to eliminate one "heretic" starat. In fact, this is a major plotpoint of Rhys's story. For a character as clever as Amy, who seems to be pulling a lot of strings, it doesn't really make sense for her to send starats on this mission. Even if she doesn't trust any humans.
There are other issues with this book, and in the end, I'm not 100% sure what this book wanted to be. Book one was so solid, so tight, so goal-oriented, while this one kinda seems like three short stories in a trenchcoat. There's definitely a lack of cohesiveness and theme. There is something here, though, and while I did struggle a bit to get through it, I still want to see where the story is going. The fact that I'm looking forward to the other books means I can't give this one less than three stars, but it does need work.