ill throw in my few cents
Survival has gotten easy, Sickness from water and food is such a None issue, i think chances of sickness/how harsh they are should go based on difficulty, like you eat rotten meat on normal you going to get sick, eat it on insane and you going to regret it
i like scavenging and crafting, and i like the books idea cuz i don't need to invest into skills just to make a better gun, or pick. but some things should be harder, like weapon parts being needed to fix weapons fully, IMO makes the game harder