Thinking about all of the fictional worlds that I've most enjoyed reading about, I've realized they are all vastly different. Downside is dark and grungy, littered with dirty, sleazy people and murderous ghosts. Mead's Dark Swan has two worlds, the "normal one" where spirits are banished from and the other where the fae live and you can find a different setting around every corner. Or The St. Croix Chronicles where a gritty underworld lurks beneath London's proper society. The people are dangerous and the air itself is so thick that it crawls inside you, making it nearly impossible to breathe or see.
But the one thing that they all have in common is their uniqueness and creativity. The authors who I consider the best at world building are the ones who create worlds that are unlike any others in their genre.
If I had to choose one world to live in, it would be C.L. Wilson's Tairen Soul. I've always had a fascination with stories featuring fey characters and Wilson's is one of the best. It's beautiful, magical, and dangerous with a medieval style setting, soaring Tairen beast, and armies of warrior fey with deadly weapons and powerful magic battling their mage adversaries who lurk in the forests of Eld. There is also the kingdom of immortal elf Seers and the Fading Lands, a magical paradise that serves as the kingdom to the fey. It's a complex, fascinating world that is filled with non-stop entertainment. Anyone who appreciates exceptional world building should give this series a try.