These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Esoteric Happy Ending: Hathaway's weapon worked. Blowing up Hathaway's house still proved that it worked; and it's shown that the CIA knew it was a problem with targeting; not the laser function. Chris had given the schematics (the dynamite laser) to Hathaway before he decided against it. Even if the original Kill Sat was destroyed after destroying Hathaway's house due to the reflected laser; Hathaway and his military contacts would have made copies of this information.
That is, unless it was subject to added public and Congressional scrutiny—see Headscratchers.
Shown Their Work: It's debatable how much is this and how much might be considered Easter Eggs, but, aside from the over-arching Hollywood Physics plot, the number of minor, technical details that are accurate probably represents how many "not-Pacific Tech" alumni crawled from the woodwork to flesh out the details of Pacific Tech campus life and the general science scenes.
Strawman Has a Point: At no point does any of the protagonists bother to exposit why it's so wrong to build a laser capable of vaporizing ground targets from space. They simply state that it is, and act on that basis.
Hathaway lied to them and used them to build weapons. It was their tech and work and he stole it from them to use to kill people. They had a moral connection to that work and could not stand the idea of their work used to kill people.
Even if building a death laser for the government is not wrong in and of itself, taking people who don't want to build a death laser for the government and tricking them into doing precisely that is unethical. If informed consent ain't informed, then it ain't consent.
The Woobie: Mitch, deliberately. His parents are so aloof and neglectful, they don't understand why a bullied fifteen year old would want to return home or why renting out his room to a stranger would upset him. Add in the bullies, the aloof roommate who is more into partying than working, the apathetic classmates who put recording devices in a class so they don't have to appear but still get the lessons, and the teacher of said class who gave up and put his lesson on a recording for the class to listen too, and Mitch was the only student to still attend in person, college was not the joy he thought it would be.