Ego isn't narcissism but can lead to narcissism if the ego is in control. To me, all ego is motion of what is motionless, ego is basically an expression of what Buddhism calls pure awareness or nothingness, meaning, ego is of this motionlessness state expressed as motion.
Ego is balance because it's neither of what is desired or undesired, only when the ego is in control is the ego of desire to be more than it is or more than what everything else is, for an example, to be more than what a judged old consciousness is, is the ego in control. To desire to be neither is ego and to just be all of what is void of desire is egoless, of motionlessness.
Pure awareness just doesn't mean being aware of everything, it means being of everything void of bias or desire. Being of everything negates motion therefore ego because once everything is as one, there is no motion because there is no separation, only oneness/motionlessness. Only in separation as in yin and yang is everything of ego, this is until yin and yang become one with each other.
Yin and yang working together is ego. Yin and yang not working together is egotism/narcissism and yin and yang working as one is egoless/motionless/oneness.
The ego to me simply represents limitations, the more of the ego we become, the more limited we become consciously, of course the more limited we become, the more destructive (hurtful) we become. I think our present reality shows this quite clearly, look upon what we are doing to the Earth and each other.
So has our controlling ways got something to do with our limitations? I think so for only the ego desires to change everything to it's own desires thus limiting itself only to it's desires.
To me, the soul is of the ego but I suppose one must experience this first hand to acknowledge this.