I agree mostly with Lynne, but you really need to make sure you can still cut someone out of their harness (i.e. the pads should not have a possibility to shift to a position where a rescuer is likely to attempt to cut the webbing)
Cutting someone out can be the quickest way in a rescue and it would seem (to me) a poor choice to compromise that.
Since the pads would be between the D rings and the backplate, should they not stay in place?, and would it not be easier to cut them out somewhere along the torso, where the strap is not as tight to the body as on the shoulders?
Safe diving