I agree. I think this would be a lot of fun and a good way to give the game some extra longevity - as well as perhaps a great way to showcase the game to friends who are on the fence about buying it. I'm much more of a story-based, single-player person, but I don't like how they're seen as diametrically opposed and poisonous to one another. In actual pen'n'paper RPGs, you could potentially fight each other at any time, and indeed the DM is constantly "PvPing", essentially.
