Since this thread got bumped, I think I’ll share some passing thoughts.
In the Lutheran view, the Imago Dei was lost at the fall (however, humans still have special dignity as we were created in the image of God). We also say that the Image of God is being restored in Christians.
Anyway, when I consider my neighbor, it is powerful to think about how much Christ loves him. In Christ, all humans have inestimable value. If Christ loved a person enough to die and rise for that person, that person deserves respect from me.