i do, i do, i do lol thats my genre. if you really just want violence i would go for gantz or fist of the north start, elfen lied has violence but i feel it tries too hard to be emotional and it just do, i enjoyed berserk but it is older (the animation shows this) and it is just the first season, so the story really doesnt end and the manga is still going. hellsing ultimate looks really nice and follows the manga story line unlike the original.

if it was me and i would go with gantz (because it got me hooked on the manga which i really enjoy.)

fist of the north star (because it is a classic, and the new versions animation is good)

or hellsing ultimate the ova is still not all out yet so this might be a negative.

here is a list:

fist of the north star, new and old versions.

berserk

hellsing (and hellsing ultimate, good animation )

gantz

elfen lied

that is the main list right now. i will add more if i can think of any