@Calvin: Try the audiobooks for your second run through. The readers are very good. They get a few pronunciations wrong in the first book, but it is corrected after that. They are very good to listen to if you have read the books (so you have an idea of what is going on) while doing other things. Your library should have them all since they are best sellers.
I just started reading Lord Fouls Bane from Stephen R Donaldson. I do not know if his fantasy world is as complex as some authors today. However, he seems to be considered a classic and alot of modern authors site him for inspiration. I think Brandon has and I think Bookstore guy has said he likes.
Alot of people on the Books forum really like Stephen Erickson. The first book did not do anything for me. People keeping saying it is the 3rd book that grabs you.
Brandon has also raved about LE Modesit. Though I have not read him yet.
Tad Williams is one that Brandon read as a kid. I think he is more of a Tolkein clone, but I am not sure. Have not read them.
I really liked Weiss and Hickmans Deathgate Series from the 1990s. They are the founders of the Dragonlance universe.
Michael Moorcock from the 1960s Elric books. These tend to be shorter. The world is not as complex. However, it is very dark and basically nihilistic. These are pretty short books.
A woman I used to work with really likes Jennifer Roberson.
It's been a while since I have read Stephen R Donaldson but he is an amazing writer, I especially liked his Mordant's Need. It was really amazing, the series is like a war against reality though it can get very graphic compared to some books and I would definitely say it is for adults (Not one but my dad didn't remember that being in the books).
And yes Weis and Hickman are amazing world builders, I have 12 books of theirs from Dragonlance and I love everyone of them.