To be fair, as Doop says, the motivation behind those actions was to try and save the mutant race. She couldn't give a rats ass about humanity certainly, but she's definitely more in the terrorist/freedom fighter mold than just some random psychotic who runs around killing people for no reason. She has a cause.
What's interesting about Mystique is that, like Magneto, it's possible to sympathize with her motivations, if not her methods. I personally find that makes villains much more compelling than someone who just kills for the sake of killing.
Anyway, she's more sociopathic than psychopathic, in my opinion.