I was just thinking, why don't Blizzard alter the effectiveness of PvP Power on a per class or even per spec basis? Look at the recent Hunter buff to their aspect, clearly it is meant as a PvE buff but it will have PvP implications to a class that is already quite strong.
If Blizzard were to change the amount of PvP power required to gain 1% of damage/healing for hunters, this would be an easy counter? I.e. it now requires 410 PvP Power per 1% damage increase instead of 400.
You could make quite small changes quite easily to a classes output this way.