I enjoyed the Flat Earth books, but I most love Lee's short story collections from the 80s (Red As Blood, The Gorgon, Cyrion). Some of her stuff can be problematic -- she really doesn't much like women, for instance, and she's got a thing about Orientalism -- but she turned out so much comforting bubble gum. It got me through my teen years.

Mentioning: Melissa Scott recently revised and rereleased her 1980s Silence Leigh trilogy as The Empress of Earth, and it's chewy fun, with bonus polyamory. :)