Sure, he's not the best dad in the world...or the universe. I mean, what kind of dad slices off his own son's hand? And who tries to destroy the planet that their daughter lives on? I mean, granted he didn't know it was his daughter at the time, but still. Vader is one cool cat. He's the toughest force in the galaxy, he knows what he wants, knows how to get it, has a red lightsaber, and is just one bad dude. Of course I'd rather him be someone else's dad in the neighborhood than mine, but he is still one of our favorites.