You TELL'em, Steve Dave!
TOO SOON, MAN! TOO SOON!
What good is a game whose server system allows everyone to be on the same server at the same time if the game isn't worth playing?
World PVP, imo, is the best, as it's spontaneous and more interesting. It's more "immersive" when you are questing in a zone and you run up on a horde and both of you make that decision of whether or not to attack. Oh, and you left out another scenario: higher level ganks lower level who stood no chance, who then logs out, grabs his higher level toon and perhaps a few of his buddies to come back and wreck shop and seek revenge.
Keep in mind that, just because something isn't fun to YOU, doesn't mean the very same thing isn't way fun to someone else. That's one of the reasons WoW succeeds even when its not always perfect. There's something for everybody in there to enjoy provided you're not focusing on the finger and missing all the heavenly glory (my apologies to Bruce Lee).