To be as brief as possible, when Wallace uses "gave Hal the howling fantods" instead of saying "really terrified Hal," I feel challenged, impressed and amused. I appreciate that immensely in an author. (Further: Pynchon, Joyce.) If it doesn't appeal to you, it is not an indication of intelligence or stamina. I am also an admirer of Henry Miller; on the other end of the stick he can be far too 'loose' for readers.
You might try Thomas Pynchon, (esp. Gravity's Rainbow) if you haven't. He is less structurally complicated on the surface, but still wields hordes of thorough and hilarious characters sifting through numerous obvious and nearly invisible plot-lines. Mark Danielewski (House of Leaves) takes the external structure exercise all the way to the graphic design/layout extreme. It's a hell of a lot of fun, but (in my humble opinion) the concept is better than the actual novel.
-still managed to be verbose. Apologies.