What are the pros and cons of hunter gather societies?
Varied diet (when food available) and tight social network that keeps bad behaviour in check.
Hunter-gatherer (H-G) diets tend to be diverse - both meat and vegetables - thus proving a nutritious diet most of the time. However, when foods is not available (e.g. a climate drought) hunter-gatherers often face starvation.
Another advantage is it tends to re-enforce what's called "pro-social" behaviour - in other words, people tend to get along pretty. Many H-G societies tend to be under 150 people and so everyone knows everyone else or is in fact related. H-G societies will often ostracize or expel individuals who are making trouble in the clan and everyone knows that this is a possibility, so they tend to not make too much trouble. In contrast, in big city states, there is more anonymity, people try to get away with more bad behaviour.
Cons not discussed, but on balance our human ancestors lived in small H-G societies for perhaps 2 million years before other types of societies emerged, so it must have a lot going for it!