You don't want to get me started about the differences between Wilde and his characters... ;P
I guess that before DH I could have believed that those two could have had some interesting conversations about the morality of transgressive behaviour and the nature of crime, but I'm far from sure anymore. After DH I have difficulty believing that Snape has any transgressive desires in him to redeem his priggishness. Twu Wuv - Wilde would call that 'tedious, dear boy, very tedious.' ;-)