Of the five short stories:

Demon Hunter: PvE mostly, with hint that there was PvP event against the corrupted DH

Barb: PvE only

Monk: some PvE in the beginning, mainly PvP

Witch Doctor: both PvP and PvE

Wizard: PvP only

Haha. This probably implies nothing. IMO the PvE fights in the stories are trivial. The obvious reason is the big ones are for us to slay. On the other hand, Wizard's story PvP fight was really exciting. ;)