Overall, I enjoyed the even pacing of the book and the story was interesting. Just a note about my review: I have not read the first book in the series. I think this book does a good job of recapping some of the first book's major plotlines when necessary, so I still felt like I knew what was happening and the general context.

The story was all pretty fast-paced; I appreciated that even in the times where there should be training montages, the book glosses over those a bit so that the story doesn't get bogged down with mundanities. Also, when there is complicated science happening, the story doesn't get slowed down by those details, either. I think this would be a fun book for younger readers. There is something constantly happening, so it should keep their attention. 

This book definitely highlights values that are good for younger readers. Most of the book takes place in a GAIA base that houses soldiers, scientists, and aliens. Many of the featured characters here are women, who are shown to be just as (if not more) capable than the men around them. The author also does a good job in making these characters well-rounded so that they feel realistic. There is a situation where a very smart woman is basically having to do the work of her incompetent superiors, and so we do see the frustration involved in that scenario and how unfair it is. Kwan, the scientist who is recruited at the beginning of the book, is also a woman who is extremely smart and skilled at combat, and who often mentions her goal of moving her girlfriend from Korea. The admiral in charge is also a woman, and although we don't get to learn a lot about her, we know that she seems formidable and that she always knows things that she isn't telling others. 

In terms of inclusivity, there are also several alien races presented. Not all of them are good, but many are, despite how scary or odd they may look to those not used to them. Sam and her friends have to learn to be respectful when they see these various races and not just jump to conclusions or be rude to them because of their appearances. It's just a good lesson in general to be mindful of others' cultural norms and how not to offend them.

I think a lot of young girls would be able to relate to Sam in general and would aspire to be like her in many ways. She is young and makes mistakes, but she is also smart and cares immensely for her friends, to the point where she will put her own life at risk to save them. Throughout the book, Sam takes it upon herself to try to solve problems on her own and not tell the adults in charge the information she knows. She thinks they won't listen and that she can do this all on her own. By the end of the book, she has to learn the lesson that it is okay to ask for help and that she can't just fix everything alone. No matter how smart she is, she is still young, and needs to tell the adults when something happens and at least give them the chance to listen. She makes some poor choices that have consequences, and so it was good to see that she isn't some infallible character, and that being perfect isn't the goal, but that it's more important to have a good heart and to do your best to learn to be better. 

In terms of science fiction, this would be a good way to introduce new readers to the genre. There are a lot of science fiction elements included - aliens, AI, spaceships, science experiments, space travel - but I think they're all included in a way that is approachable. A lot of the focus is on the action, and so the science parts are explained quickly in ways where you don't need to know actual science to understand what's happening. As such, I think it's nice to make science feel like an exciting thing where anybody could participate as long as they study and can be creative in their thinking.

From an adult perspective, I do find it a bit annoying when characters as young as 13 act like they should and do have the agency and knowledge that an adult should have - but I know that's just part of the genre. There were also some inexplicable and overly-convenient plot points that could have been better. I think one of the more blatant examples of this is when one of Sam's friends pops out from a hiding spot in the ship that they're in after hiding there for way too long unnecessarily. He explains himself jumping out at the last minute by saying that he was waiting for the "right moment." But this presumes that he just watched from a vent as his friends: 1-fought off enemy soldiers, 2-brainstormed to come up with a plan to fight the main bad guy after the immediate threats were killed, 3-left the ship to go enact their plan while leaving one person to figure out the ship's controls by herself, 4-watched this last person also leave to help her friends escape a collapsing cave, 5-struggled to drag a heavy, unconscious adult back to the ship, and then 6-talk about how they were even going to drive the ship because they didn't know how. Only after that does he pop out with his weapon and say he can help these two teenagers with their problem. There were a few moments throughout the book like this that were a bit confounding that could have been written better. But as stated before, because this book's strong suit is its constant, quick pacing, it moves onto the next issue quickly so you don't have to dwell in these types of frustrating moments, and I don't think they would be a big deal for those just looking for a quick read anyway.