Although in the larger context, there Buffy/Angelverse repeatedly asks the question, when you've committed evil, when you've /been/ evil, and want to change, or actually do change, do you get to? Are you the accumulation of your sins, or is redemption possible? Can you be unforgiven and still be worthwhile as a hero? Does existence precede essence? Granted, that's more AtS then Buffy, but still. Anya, Faith, Angel, Faith, did I mention Faith? ANd of course, Spike. Spike isn't the only one who did the Evil to Good transition (with some bobbles along the way), and so reading his (limited) forgiveness as somehow a whitewash -- no, I don't really see it.