Reset Approval Path for one person and for only pending

Sometimes only parts of the approval path will change, like the person or the order. I would like to be able to reset approval paths for only pending requests and only for that one change. For instance if there are two approvals prior to the step you change, they should stick. It would only reset for all pending requests from that step forward. Or the ability to have a drop down to reset for All or Pending and another for "step" to start over to choose which step.