If that was my clavicle fracture I would have it plated, especially if there is any tenting of the skin. That may not heal as it is completely displaced and even if it does heal it will be a malunion. In any event I would go see an orthopedic trauma surgeon in your area for a second opinion.
I agree. If it were mine as well, I'd have it pinned/plated. Just because of how active I am and how active I want to be, I don't want the pain to keep me from doing stuff later down the road. No guarantees the pain will be completely gone even after pinning, but at least the chance of your shoulder getting so much better functionwise will be significantly higher than leaving it be.