Remember, you yourself said there are three value systems at play. Alan Moore wrote Rorschach as a fascist, and Alan Moore clearly believes that fascism is not a positive value.
But Alan Moore’s readers are free to have their own opinions of fascism, and treat Rorschach as a hero if they think fascism is a virtue.
Same thing is true of other similar characters, like The Punisher.
I’d even argue that in the value systems of his world, a fascist characters like Judge Dredd is a paladin.
(Admittedly, all I know about Judge Dredd is the recent movie.)