In terms of the story, I thought Primal Mirror didn't do an especially good job at balancing the individual romance with the evolving mythology of the Psy-Changeling universe. Like the Psy-Changeling Trinity novels have been heading towards a complete collapse of the PsyNet -- a psychic plane necessary for the existence of all Psy people -- which would basically be a global genocidal event if it happened. We get glimpses of that though some random pov asides from Ivy Zen or Kaleb Krychek, but mostly the leads, Remi Denier, alpha of the RainFire pack, and Auden Scott, daughter of psychotic Psy Council members, are wrapped up in their own concerns and don't even seem to be aware that all the Psy (including Auden) might just fall over dead in a week or two.
I found Auden's character honestly interesting. She's a psychometric -- a touch-psychic who can read impressions from objects -- from a family of power-hungry psychos. Because her parents didn't see her more passive ability as useful, they used Auden as a guinea pig in some fairly horrific experimentation on her brain, the ultimate violation for a race whose greatest gifts reside in the mind. Auden has been healing for the last few years, and more or less comes back to herself while 7 months pregnant, completely unaware of how she got that way or what even is going on. And she's in a Scott family den of vipers still loyal to her horrible mother.
Auden ends up being the ultimate unreliable narrator, even to herself, which is an unusual narrative style for Singh -- mostly her characters are presented in a straightforward manner. As such, I thought Singh hid the football for a little too long, long past when I figured out what was going on. I don't think there's much narrative tension in a secret both the author and the reader knows, but the characters don't. (Maybe as a Psy-Changeling superfan I have more insight than the average reader, but I don't actually think so.) Remi and Auden's courtship takes place through her third trimester and into the first month or so of her baby's life, which struck me as somewhere between ridiculous and weird. Like Singh makes a lot of noise after the baby is born about how Auden got a bunch of nanobot healing nonsense. Which is fine, but when Auden starts begging Remi to have sex a week after giving birth, I was like, girl, this is ill-advised.
Remi is also straight from predatory Changeling central casting: a little bit of a tragic backstory but still a himbo, protective, possessive, and utterly basic. I didn't particularly feel the snap between these two, which would probably be fine if the story were more about the race to keep the PsyNet from disintegrating. Alas, it was most about Auden's memory-hole and what jerks her parents were. But I'm usually less interested in stories that revolve around the Changelings, so I admit I'm biased from the jump.
Which brings me to a quick bitch I have about the Psy-Changeling world more generally: how the hell do the political/governmental systems work? There's a number of globe-spanning orgs -- like the Psy Council, the Trinity Accord, the Arrows, the Forgotten or the Human League -- but each of these groups seem to have like 3-12 people in upper management, and virtually no administrative state. I see no evidence of what we would consider nation-states, and each of the races seem to self-organize? How the hell does any of that work? Maybe because I'm a civil servant myself, but I legit don't understand how basic stuff like birth certificates or driver's licenses are administered.
And look, I get how nit-picky this is, and how little it matters to the emotional realities of the romance plots that make up the Psy-Changeling world. I just notice it more in plots like the one in Primal Mirror, which hinge on Auden somehow being both the all-powerful head of her PsyClan, and utterly powerless i/r/t her dead mother's lackeys. Just fire them? Hire new lackeys? Surely this medical experimentation is illegal as hell? And if not, why not? It felt a little like Payal Rao's situation in Last Guard, but that actually made sense to me: Payal's psycho dad was still around to pull the strings.
I feel like I wouldn't have hared off into completely esoteric nonsense if I'd been more on the hook with the central couple. When my brain starts fixating on dumb bullshit that ultimately doesn't matter, it's usually because something bigger has gone wrong: the little problems stand in for the big ones. The big problem here was that the central couple was mismatched and not very interesting, on a backdrop of much more interesting and dire shit going on in the world. Primal Mirror isn't bad, but it also isn't very good. Alas.