Soul is not the ego. Not initially anyway. Soul is the Self that remains the same no matter what you go through in life. It is the 'I' if you will. Ego is the false self that goes through many different phases only to merge to the original Self. It is the 'Me'. For example, when a child is born, it has no ego but just the Self. That's why it is so adorable and innocent because it has not developed a false self yet. But as it grows up it continues to acquire the false self. The journey is to find the Self and eventually make the tradition to it. The ego is important because through this journey you learn and come to realize who you truly are.
I will explain more as to what I know and see if you can relate to it. It's really best to look at things from a point where you can disassociate yourself from any pre-existing belief systems. That's the best way to learn. You can use all others such as religion, science, you personal life experiences etc. as a reference point.
I'll have to re-read everything that you've said and process it slowly to come to a better understanding of what you mean. At this point I think we are using different terms to describe the same thing, and I did leave the heart out, but I will compose my thoughts better in order to explain what I mean.