Kuyaba and Fun Holiday would both be good choices. Kuyaba has perhaps the most upscale restaurant in Negril so there are not too many single partiers hanging around - more of that at Fun Holiday. I love the big bamboo bar on the beach at Fun Holiday and I think they have a new swim up bar now. The bar is great for people watching and they set up tables for dinner right on the beach in the sand.

Consider Hedonism II or III. You'll have great fun there.