You know, aura should work like a persona. it's literally yourself made manifest. If you accept and love yourself it'll cooperate, if you don't it'll fight you. Emotional peace equals strength, emotional disturbance equals weakness. Throw in some Star Wars and Evangelion for good measure.
With Naruto we have the ninja arts, the Samurai layering of Chakra, the Monk infusion of chakra into the body. Different designs for different uses of Chakra. For Aura, what is Aura about at its core? I once saw a RWBY CK quest where high level Aura gives a cool inner avatar form manifesting the divine light of the person's soul.