I was very clear that Loki is a good counterargument to my point regarding Wanda, because in most fans' eyes Loki has been redeemed. But again, I think it's what we can visually see and know, versus what we speculate. Yes, Loki wanted to eradicate the Ice Giants but didn't. Loki did kill Coulson but Coulson had a gun he was about to use on Loki. Loki's actions presumably killed thousands in New York but Loki would argue it was a war and Earth was refusing to surrender, and we don't really see these deaths. Additionally, Loki may have done evil things and many people died as a result of his actions. But he wasn't intentionally cruel or violent.
With Wanda, she knowingly used an evil book, became corrupted by it, and then violently attacked and murdered numerous people, sometimes in cruel and unnecessary ways (i.e. Black Bolt). I think a person can look at both set of circumstances (with Loki & Wanda) and see the differences, even if we all agree both of their actions were evil.