Adult anime with epic battles?

I'm interested in getting into anime, after pretty much exhausting all of the good action and sci-fi Western animated shows. Thus far, I've really enjoyed both Street Fighter movies and the battles of Dragonball Z. I'm looking for something similiar to DBZ, at least as far as the combat/action goes - giant, epic, planet-destroying mive battles. I'm also hoping for something more mature/adult - I watched Naruto and, televised at least, it was too juvenile. Is there something more serious out there that has great, superhuman battles? I've also watched Cowboy Bebop, and I loved that, and the fight scenes were great, but not as epic as I want. Any suggestions?