Brandon Sanderson is the best of the newer authors. I am excited that he was chosen to finish for Robert Jordan. In my opinion, he rates above Jordan - especially the later books.
Raymond Feist
Roger Zelazny
Ursula LeGuin (Earthsea)
Patricia McKillip (Riddle-Master of Hed)
Aasimov’s Foundation
E.E. “Doc” Smith - Lensman series
Saberhagen’s Swords books
Finally, one who does both genres well: Orson Scott Card (Ender and 7th Son)
The Earth Sea series did not appeal to me, but she has written some excellent things. The "Powers" trilogy was excellent.