Hopefully they find a way to balance it out. Warriors definitely shouldn't be running mage armor without sacrificing some offensive capabilities or maybe a different type of defensive ones. I think making some of the buffs require specific things, like Mage Armor requiring a mage item equipped in the chest/hand/etc. So if they want to run that spell they have to wear basically a robe without the high defense/resists that the leather afforded.
I don't even know what to do about frenzy, that ability was just bonkers and basically required on both characters I played just for the movement speed. I'm sure they will do some balancing on that.