"Horrible, Horrible Disappointment - Skip It"
In this novel, Niven is mostly concerned about sex (rishathra, sexual practice outside one's own species but within the intelligent hominoids). He even created a vampire being whose pheromones cause similar races to have an uncontrollable desire to have sex with them.
Rishathra is used as the basis of sealing negotiations, birth control, forming alliances and just meeting new people. It is sad how obsessed with sex Niven is in this book. I have been told, the third book is even worse (and he doubles down on rishathra), so I am giving up on this series.
Moving past rishathra, it was a weak story. The Ringworld is larger than 3 million Earths, yet Niven generalizes it down the societies that live there into simple terms very quickly. His characters figure it all out too quickly and easily. There is no surprise, mystery, suspense, awe or wonder in this novel. A fairly straightforward story with not much imagination. I didn't even care about the characters.
The best part of the series is the idea of The Ringworld itself. The story Niven weaves around it is not worthy of his great imagination. I have been a fan of Larry Niven for a long time. His short story collection, "Stories from Known Space," is some of the best pure SciFi of all time.
On the bright side, I really liked the narrator. Paul Michael Garcia did a great job.
The first Ringworld novel should have been the last.
Don't waste your time on this book. It will only tarnish your memories of The Ringworld.