Most of it is difficult to read nowadays, it’s mostly about spreading the idea of communism to the outer space and coping with the ideologically immature alien nations. But there are some gems, of course. Strugatsky brothers as a fine example, they started to write on early 60s and even thought their early prose is full of communism ideology, the overall quality is amazing. Check their “Hard to be God” book, it’s one of my all time favorites.