Well, Ibara no Ou is kind of dark, and it features dystopia so I guess that could interest you, although I strongly recommend you to read the manga instead of watching the movie. It does suffer from terrible CGI, but it's manageable.
Ayakashi is a collection of japanese horror stories, and it also has prequel of Mononoke, which is a masterpiece IMO.
Kara no Kyoukai is a movie serie which is mostly fantasy/thriller/action with some romance. The quality of the movies varies quite a bit, but parts 4, 5 and 7 are great.
Shisha no Teikoku suffers from a shitty story, but it has one of the best artwork I've ever seen and it features zombies and steampunk. Who doesn't like those?