Berserk would definetly be number one. And, as previously stated, Battle Royale would be a good choice as well (though I've talked with quite a few people who "have problems" with the art style - I personally like it, but oh well).good art, and lots of action, blood and guts in your face stuff with cool main characters.
Anything drawn by Hara Tetsuo, such as:
- Fist of the North Star (good art, lots of action, blood, in your face stuff, cool main character, etc.)
- Fist of the Blue Sky (amazing art, lots of action, blood, in your face stuff, cool main characters, plus a decent storyline)
- Keiji(same as the others in the art/action department, very good storyline since it is a kind of historical look at the Sengoku period of Japan with the Keiji Maeda character wandering around and defeating bad guys and stuff)
The only problem with these choices is that apparently there will be no more volumes released until some other company decides to pick them up.
Also, I hear Viz liscensed JoJo's Bizarre Adventure, which sounds like something you'd like. Sadly, I learned Viz is skipping the first 2 series of JoJo's (aka: the first twelve volumes) and heading right for series 3 (I'm guessing because it is the most popular around here). As long as they don't cut anything out (which they already have for their Advance Line series, disturbingly) then it looks like a perfect match, particularly for the "blood and guts in your face" sequences.