He didn't think well of the state of European philosophy, but "despised all that went before him"? Not at all. He didn't think very highly of his contemporaries working in European philosophy (and politics), but was deeply embedded in classical philology.
> rejected Western values of good and evil (obviously, and as some here do)
That's a broad brush. To use a slightly narrower brush, he starts from the (by no means unique!) position that no God is the source of morality in the world.
> and left the reader with nothing beyond the essence of an Aleister Crowley "do what thou wilt" disregard for the idea of objective good and evil.
Sigh. At the heart of Nietzsche's philosophical project are attempts to re-ground morality on something other than the crumbling foundations of 'Western values.' He gave you a dozen books with which you can think along with him and try to solve that problem.
If you can't get more than 'do what you want' from reading Nietzsche, that's not his failing.