I find with large scale Sci Fi in general the characters are not really people so much as representatives of aspects of humanity. A person might stand for humanity’s compassion or their laziness or their determination. They embody a collective and that makes their personality as an individual suffer. Three Body Problem has great ideas though its scope is so large it’s difficult to connect to what’s happening in the story. I especially liked what happens in The Dark Forest around the 85% mark but there’s a lot of setup to reach that payoff and it is a slog to reach that point.
I’ve always liked how practical Katniss is. There is a scene in the first book with Katniss bringing meat back from her hunt in the woods, and heading to the government first. They are starved for meat just as much as the rest of the District is, so she can get them to turn a blind eye to her illegal hunting if she gives them the first cut of meat. She also knows where she can offload questionable meat (i.e. dog) to turn a small profit. Katniss is the breadwinner of the house, and though the world conspires to make her into a icon on a pedestal, she is proactive enough to make her own choices and deal with the consequences.