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.
Heartwarming Moment: After Sax is captured by the metanats in Green Mars and the underground—Maya, Nadia, Nirgal, etc—discuss the difficulties of rescuing him and the fact that information on their whereabouts will certainly be forcibly extracted from his brain, one of them concludes the discussion with "Besides, it's our Sax."
Moral Event Horizon: Phyllis, when she sides with the metanats and helps them hunt down her fellow First Hundred. She has Arkady Bogdanov and the entire city he's based in immolated by raising oxygen levels to an extreme and igniting it. It's actually debatable that that was her idea: she clearly knew it was going to happen, but may not have had the power to prevent it. It goes without saying, YMMV. The question of whether Phyllis is a monster or is merely a fool who made a deal with figurative devils is something of an in-universe YMMV for the First Hundred (one among many).