Turbine has mentioned plans for different PvMP setups as the game expands into new areas of Middle Earth... I'm hoping for it, personally. I don't spend a lot of time in the Moors, but certainly giving people more options isn't a bad thing.

I just never really felt like I had enough of an investment in a monster to play as one. Sure, you can learn new moves and so forth... but preventing normal characters from getting places just because doesn't strike me as significantly interesting.