I've only recently gotten into the Star Wars mythology, and I can't help but notice how much Anakin/Vader resembles Arthas. When you REALLY invest into the lore of both franchises, you can't help but grow to detest Arthas because he is basically Anakin Skywalker, stripped of the compelling characterization. Yes, the characterization of Arthas leading up to him becoming the Lich King, just pales to Anakin becoming Darth Vader.
So all in all, why do you like Arthas?