MsPenny - I have one shoulder which rounds in and is elevated off the ground when I'm lying flat. The muscle under my clavicle on that side is very dominant and almost non-existant on the left. My clavicles sound like yours as well. They are not symetrical but were symetrical before tos.
Up until June or so, I was only doing hands-off Physical Therapy and failing. I found an excellent manual therapist and my clavicles look very different now. The bone definition is more pronounced and they are looking more and more alike. I still have a long way to go, but positive visual changes are happening. I don't think you're alone in your observations. Why do so many doctors blow us off when we point these anomolies out to them?