(Might add to these, don't think I've really captured the impression that I want to capture!)
* Picaresque space and/or soap opera. Very assured, fluent, immersive, effervescent ensemble story, prolapsing the domestic sphere and squirting it through the cold vacuum of outer space. Reconciling the domestic and the epic. Cozy af.
* Retrofuturistic. "Soft." Kryptonite to the "calculate Delta-V properly" crowd (actually they probably don't like it when you say kryptonite properly). Perhaps it's a little postmodern too. Cf. Scalzi's Redshirts, the 1999 movie Galaxy Quest. The pretense of future history is thin to non-existent. Rather than making estrangement into a formal framework (cf. Suvin), it makes cosplay, dress-up, make-believe, theatricality, group-selfie-as-interpellation into a formal framework.
* Perhaps cf. Karen Lord's The Best of All Possible Worlds. Similarly flexible pacing (e.g. a big space battle and buying some soap may in principle loom equally large in the narrative). Similar pleasure in gentle, small scale didacticism, and drama that involves tiny moments of (find a less teleological way to express this but) personal growth.
* And of course cf. Jo Walton.
* Even here though I feel a few tremors from the great xenophobic anxiety that is rumbling through so much sf nowadays. Cf. Emma Newman's Planetfall. But I was very fond of the health and safety vibe of the resolution: I don't care what geopolitical bollocks you elites have got yourself mixed up in, the basic safety of workers comes first.
* Structure of friendly misfits bungling along together, occasionally zooming into the backstory of one or the other, as relevant. (Rosemary feels like the protagonist in the same way as, say, Pipes is in Orange is the New Black).
* I think we should be very careful before dismissing the squeeing millennial personality structure of the novel as a weakness (or no doubt as many people think of it, as a deal-breaker). Surely this most distinctive feature is both central to the experience of those who take lots of pleasure from the novel and to those it most offends potentially evidence that they are not yet reading it competently. But yes, it is certainly a book that requires not only literary theory but also fan studies to be understood properly. It is Fans in Space. Mock heroic and Sontag's camp might frame aspects of it, but they don't capture the full thing.
* It is positive, optimistic, filled with kindness and inspiration. Sometimes its kindness is of a kind that is associated with privilege: kindness, inclusion, courage, wisdom, diversity, but only so long as it doesn't threaten the existence and the delight of the in-group. Stops short of decolonization, or long term engagement with political activism. (The West as fandom). I say it is associated with that, but perhaps that's where the "in space" bit comes into play. You can't merely sneer at this kindness for being founded in privilege, because part of the alchemy of the storytelling involves thoroughly disarraying the socio-economic foundations of this kindness. You kind of have to judge it on its own terms.
* Perhaps it is necessary to re-theorize immersiveness as the [book-] group hug. (Cf. the vague notion that the most immersive world is the world that has been most thoroughly "built"). Cf. C18th sentimentalism. Much open weeping. Of course to say that the cult of sentimentality is shallow is to say nothing at all, it is not even to reach the depth of shallowness.
* One way of thinking about this book is to think about its morality. Don't pigeonhole it as identity politics soft leftism, actually have a proper poke around and work out what's being said. And in matters of moral microguidance, be careful not to place undue weight on originality. Okay, so perhaps we have seen most of the ingredients of these little moral-emotional situations before, but what's important is the specific ways they're combined here.
* It is anti-heroic while being diametrically opposed to the dominant form of anti-heroic fantastical literature at the moment: grimdark.
* I've heard its like Firefly, which I haven't seen. But it felt a bit like Star Trek meets Buffy. So if Firefly is at all like Star Trek meets Buffy, then yeah it's a bit like that! But also, it's not quite core Whedon dialogue is it? It's not as wisecracky.
* And it's not as eyebrow wagglingly genre savvy and knowing as a lot of Whedon-influenced stuff. Kizzy narrates herself pretty forcefully, but there isn't the kind of nihilistic "we're space heroes and we're good guys" hamming and flirting with the fourth wall you get from, say, that Suicide Squad trailer.
* Cf. BuzzFeed Yellow or something.
* Agree 100% with all the one-star and five-star reviews, and none of the two three fours.
* Is it sometimes hyper-USian?