I'd definitely have to say Faith/Eliza Dushku. As a character, Buffy did have a few more positive things about her than Faith, but Faith didn't have nearly as much screentime as Buffy so in a way it's not really fair to judge. As far as actresses go, SMG and ED are both fantastic actresses, but I'm personally a fan of Eliza more. Though I love Sarah's movies, I just don't seek out to watch those like I do with Eliza's. And as far as beauty goes, Eliza's got that one for sure.