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.
Complete Monster: Thatcher. Although it's steadily implied he's a Jerkass, it really starts to become obvious when he kills his own 2 year old son because he didn't want to be bothered by child support or the harm a love-child could bring to his career. Also he tried to destroy the human race.
Designated Hero: Geoffrey Binswanger. Despite spending most of the story at a university mocking the existence of the island where the other main characters endure great dangers and suffer the loss of many friends, he is clearly set up as a hero who gets the girl despite only showing up in the third act and doing almost nothing heroic.
Moral Event Horizon: Thatcher arguably crosses it right off the bat when we find out how he set up the death of his own son to remove the inconvenience of a love child. However, if this doesn't count, he steps over once again when he deliberately releases Henders Rats onto the ship, hoping that they'll lead to the extinction of humanity.