In choosing a successor which do you consider more: competencies levels as excluded from performance report -OR- department manager recommendation?

A good Succession plan is pro active activity certainly it requires many criteria's to be considered. It cannot be based on either this or that. These criteria are more important ;like Performance Management results, Competencies, over all relevant experience,  nos of years with the organization, leadership positions handled in past and many more..  hope this narrative will help you. All the best.