I've been re-reading some of my Darkover books by Marion Zimmer Bradley, and reading some of the newer ones I never got around to.
Darkover holds a special spot in my SF heart. Like many of Anne McCaffrey's books, these are technically called, "planetary romances" rather than straight SF or fantasy.
MZB wrote or sponsored something like 30 Darkover books. They're interesting, because many of them are inconsistent with each other. The premise and science of the books are pretty iffy, mostly because they are based on some of her juvenile writing (that is, written when she was very young, not written for juveniles), but the characters and world are compelling anyway.
Some of the themes are: ethics and composition of a telepathic society; new technology (represented by the Terrans) v. traditional mores; and, of course, being MZB, the position of women.
One of my favorites is
Exile's Song and its 2 sequels.