I don't know too much about the Star Wars universe since i've only really enjoyed the recent trilogy + Rogue One BUT if we think about it, most villains are just shallow evil for the sake of being evil kind of people, so when someone can fulfill the role of great evil with a purpose, often times the villain with gain more followers and respect than a good guy with a similar drive, I will be a Sith that people can look up to and feel inspired by more than any goody two shoes could do, and my empire will rise!