Neal Stephenson: Anathem http://en.wikipedia.org/wiki/Anathem
The Baroque cycle http://en.wikipedia.org/wiki/The_Baroque_Cycle
China Mieville: The Bas-Lag books in particular http://en.wikipedia.org/wiki/China_Mi%C3%A9ville
I enjoy Robin Hobb (including her work as Megan Lindholm), despite its pretensions http://en.wikipedia.org/wiki/Category:The_Farseer_Trilogy
http://en.wikipedia.org/wiki/Liveship_Traders_Trilogy
http://en.wikipedia.org/wiki/Soldier_Son_Trilogy
For a delightful tonic, I heartily recommend Jonathan Strange & Mr Norrell . The first novel by British writer Susanna Clarke. http://en.wikipedia.org/wiki/Jonathan_Strange_%26_Mr_Norrell
Jorge Luis Borges is a breathtaking fantasist, the Dali of the short story. His fiction is life altering. http://en.wikipedia.org/wiki/Borges
Mervyn Peake wrote the magisterial Gormenghast at about the same time that Tolkein was in the ascendant. http://en.wikipedia.org/wiki/Gormenghast_series
Robert E Howard's Conan is great fun, and can be appreciated on several levels. http://en.wikipedia.org/wiki/Robert_E._Howard
Scott Lynch is compulsively readable, and a master of intricate plot lines. He writes fantasy crime capers of subtle depth. http://en.wikipedia.org/wiki/Scott_Lynch_%28author%29
Fritz Leiber http://en.wikipedia.org/wiki/Fritz_Leiber wrote awesome pulp, and was a far better stylist than his beloved Lovecraft. http://en.wikipedia.org/wiki/Lovecraft
The Chronicles of Prydain are simply lovely. Avoid the dreadful Disney movie. http://en.wikipedia.org/wiki/The_Chronicles_of_Prydain
Ursula Leguin will still be the focus of doctoral theses a century from now. Her science fiction is as significant an exploration of the human as anything by Proust or Sartre. http://en.wikipedia.org/wiki/Ursula_K._Le_Guin Earthsea is a good starting point, but don't hesitate to read her more speculative stuff.
Gene Wolfe writes lies, in the best possible way. Nothing is as it seems in his works. http://en.wikipedia.org/wiki/The_Book_of_the_New_Sun He wrote some very profound short stories that are still revolutionary.