I would like to make a suggestion that each class specialization at some point over time becomes immune to the same type of spell that causes a loss of control over their character as long as they are of the same specialization.
Ex. Frost Death Knight would become immune to being Iced over by a Frost Mage and lose control over his character.
Rather this immunity comes within the first spell or a few spells later, it should just happen. It is wayyyyy too ridiculous trying to PvP with every single class causing loss on control over your character. You only have 3 at the very spells/trinkets to stop it from happening and those have cool downs.
I have talked about this with several people in battle grounds and I have yet to find a single person to disagree with it. Please consider this for the sake of PvP.