Hey, well, that's a title with a lot of heavy lifting entailed.
Having committed an English Literature A-Level, I grew to really hate the incredible level of
Much literary criticism comes from people for whom extreme specialization is a cover for either grave cerebral inadequacy or terminal laziness, the latter being a much cherished aspect of academic freedom.
~John Kenneth Galbraith
...ouch. But, pretty much.
My personal feeling is that books read best when there's a whole lot of stuff going on just under the obvious that your subconscious can gnosh on, and another feeling I have is that when you pull all that good stuffing out into the light of day, a lot of the magic of reading is gone. Because, O Reader, you know what? 95% of brain activity takes place below the level of conscious awareness. Yes, you read that right; 95% of what your brain does, you know eff-all about, and the leading scientists don't really know much more than eff-all - but I admit their guesses sound a lot fancier.
So how the hell does all this opinionated crap tie into Through the Hostage?
Well, first of all, I hope the book took you to strange new worlds and dropped you in them hard enough that you could smell the jungle. Second, because a lot of Cortiian interaction is deliberately designed to be show. Watch Khyria in public. Whatever she's actually saying is the cute, glittery bit of the iceberg on the National Geographic cover. Underneath that there's the history, the public image, the private agenda, and let's not forget the Cortiian staple - power politics.
War, therefore, is an act of violence to compel our opponent to fulfill our will.
~Carl von Clausewitz
In case a reminder is needed, the Cortii are professional mercenaries. Everyone goes armed, and the most common method of advancement in the ranks is assassinating the person whose position you want. A lot of time on a Cortiian Base is therefore spent making certain that your position is unassailable. Everyone has a different take on how best to do that. Senja Ventiva opts to make certain that there are always more powerful people with a vested interest in keeping her alive than seeing her dead. Anst an Nabat ensures that he mostly knows well in advance who's gunning for him and why. Khyria Ilan uses the rumour mill to her advantage, and makes sure that most people are certain she'd sooner shoot them than give them the time of day.
One need not destroy one's enemy. One need only destroy his willingness to engage.
And let's not forget, in Through the Hostage, Wildcat is still in Basic training. Cortiian Basic training lasts between seven and ten years, and along with all the things you'd expect to feature, like physical training, combat training, game theory, military strategy, psychology, politics, etc., Cortiian Basic training is designed, bluntly, to break people. Recruit casualties run very high, and ensure that the stupid, the inept, and those who simply don't have the resilience and flexibility to be able to do damn near anything on command don't survive their first year.
The only rules that really matter are these: what a man can do and what a man can't do.
~Jack Sparrow, 'Pirates of the Caribbean'
That's the backdrop to Cortiian society. It forms the undertow to a lot of Through the Hostage. Taiva Zarlan forms a good case in point: she's intelligent, competent, and she's survived seven years of Cortiian Basic training. Despite that, she has lines she still won't cross.
“I can’t murder you and I may not be able to murder anyone else, but for the sake of completeness you should find out whether or not I am capable of murdering myself.”
~Taiva Zarlan, Through the Hostage
On a Cortiian Base, that makes her, to some extent, a target. Not only does Taiva have limits, which can be discovered fairly easily if she's pushed, but she doesn't have any influential allies apart from Khyria, and she's not, as Khyria is, widely known for being much more trouble to try and kill than she's worth.
So, to go with the Dumbledore method of announcement, the themes in Through the Hostage are: 'Survival! Independence! Trust! Dominance! Fancy fight stunts!'