Costumes / Hat OFF?

I just wanted to ask if there will be a way to wear a costume that covers and does not replace armor. As in that you still have the same armor value, but are wearing instead of a bulky heavy armor a military uniform.

The second thing is what I call a Hat OFF function for those who would rather show off their hair. It has been implemented in many video games already that this let the hat vanish, even though it is still equipped.