Which of three successful head coaches has the best future

Out of Bill Belichick, Mike Vrabel, and Jim Harbaugh, who will have the most instant success? It's easy, whoever gets the Chargers job. It sounds like Jim Harbaugh will get the job and is having another interview. Justin Herbert needs a good coach and someone to change the entire culture. Who wants to work with Belichick? He probably wants full control.