Yeah. That,s my point exactly. Mlakavians can either be used as comedy relief characters (as my first was- he had a sock puppet thing going on) or very disturbing characters to bring the game into more sharp focus. I find the easiest way to run an insane character is to give them singular, independant insanities.
ie. bob has a second personality, chronic depression and a manic fear of puppies
instead of: bob is fucked in tha hed.

My current character is also a malkav purely cause I wanted to see how much I could push a serious character on my companions. He is perfectly sane at the moment except for a belief that he does not need blood. Very dangerous of course for a vampire. Whenever he reaches zero blood points he has to take a willpower test every time he sees a mortal. If he fails he drinks and forgets it afterwards, but if he fumbles... well that's a new insanity isn't it.