I think high-level PvP is just plain more fun. It allows you to multi-class and really diversifies the PvP experience as you are no longer bound by stats limitations and can change your equipment and strategy to your liking at any time.
It might be more fun but that is also one of the main reasons of why there are parts in the game in where you can't go with your character revived online to certain areas. It doesn't help either that a lot people that likes to invade use the Ring of Fog, that's easily one of the worst items in the game.
It barely serve any purpose when you are not playing online. Is as annoying as the Situational Awareness booster in Uncharted 2 Multiplayer.