Exactly. Precise subtlety of thought is extremely difficult to bring off in a film without creating something most people find either boring or incomprehensible. When I described Rawhead Rex as being a classic monster film, I meant in the old school sense of the Universal horror titles. Simple but enjoyable. The archaic mythos and sense of dread Barker incorporated in his original work were entirely missing.
Some of the books in Neyjour's links reminded me of Kim Newman's Anno Dracula. I'm not sure if it's still in print, but if you can find a copy, buy it.