First would like to say sorry for all the problems you are having. I have never heard or have had a converter not fill up all the way. Making it out of balance. Make sure your converter bolts are tighting all the way. They maybe to long or your converter lug threads not deep enough and the bolts are bottoming out before they are tight. Also make sure your front pump bushing is not worn out
But to me if it was worn out enough to make it vibrate that bad. That your pump seal woukd be leaking