The best part about Dune is that it's really one of those books that reveals different things every time you read it. It should be part of every serious literature course.
I'm sorry, but I have to challenge such a broad statement. The classification of literature is an awful game but Dune is hardly a default candidate for serious study, and I feel a view of literature with it near the top is unfortunately stunted. Just speaking as someone who has taken many of the courses you mention, although not an expert.
If nonsense like Pride and Prejudice makes it into a literature course, Dune at get above that low bar.