the ultimate battle of good vs. evil: balanced karma

ok, my brain has had too much time to ponder stuff, so I get into these thoughts which are my mental lint. what exactly does it mean to balance one's karma? Karma translates to mean deed or action, so it is the application of the basic spiritual principles in which to live by, e.g. the golden rule, unconditional Love and Goodness, etc.

So, it would seem that the point then to balancing out our karma is to either (a) have a 50/50 mixture of good and bad deeds or actions; or (b) nearly 100% good deeds or action. I am stuck trying to figure out what the whole 'balancing act' (ha, pun intended) is supposed to be about. Somewhere in my mind I've picked up the idea that in order to return home to the Divine (that is, become a completed soul and break free of the birth-death cycle) that we must become pure again. Would this mean being as totally 'good' as possible, or is it simply enough to be about 50/50? If the Divine created all that we see and hear, then it is logical to conclude that She is both Good and Evil, Love and Hate. Does that mean we are to also be in this seemingly contradictory state of existence in order to go home?

Another thing is, karma isn't exactly like Newton's Third Law, that for every action there is an equal and opposite reaction. If in this life you are a hateful, angry person who likes to sling verbal insults that doesn't mean that in the next life you'll be on the receiving end of such abuse. As how I understand it, you can 'balance out' such karma in this life through 'good' actions or deeds, or perhaps in the next life you will be a person who is dedicated to helping people not be angry assholes who sling verbal assaults. There seems to be the notion that through karma we have the potential to learn life lessons if our free will permits us to, and often it seems the reason we don't permit ourselves to learn these life lessons has to do with Ego being so full of self that it won't permit anything that will in any way diminish Its importance.

Is the real culprit then our Ego and not our free will? The spiritual philosophy of surrender to a higher power, to your higher self, or to become the no-self in Eastern thought, all points to the abandonment of the Ego and a return to the One. Does then karma prepare us to release ourselves from the grip of the Ego/Self? I think that it does, that by doing kind acts and by being kind and loving, the Ego can't help but to dissolve away leaving our purest state of being: a Light of the Divine.