This is actually really interesting because I tend to love those characters too (though you mentioned wanting them to have a sadistic nature but none of the characters you listed were sadistic?) yet I never got too attached to the ones you listed. For example, I got attached against my will to Sasuke XDD
Although I must say that while Homura is misunderstood, I don't find her to be an anti-hero.
As for Itachi,
As for Kikyo,
OMG sorry for rambling!!!
Okay, suggestions!! Basically, you don't exactly want anti-heroes, but furtive characters whose motives are, unbeknowst to most, are pure.
Have you watched
"Avatar the Last Airbender" yet, by the way?
It's not quite how you described, but I think you'll love Zuko, especially in the middle, you'll see a huge inner conflict. And the show itself is amazing.
Also, you might be interested in Kida Masaomi and Celty (<--female) (like this in the beginning I would say?) in the anime
"Durarara"
And a lot might disagree, but despite it being a shoujo and somewhat slice-of-life with the one fantasy element,
"Fruits Basket" has A LOT of these characters male and female
I'm not sure if that'll have exactly what you're looking for, but those are a few of my favourites and contain characters that I believe fit what you're looking for.