I would prefer an NFL experienced replacement.
Jerry and Stephen will always have their radio shows and press conferences, but a coach who is given team authority can easily overlook that.
A new coach has to be able to hire his own staff, that will be the number one indicator as to how much control he has negotiated for himself. Loyalty issues are paramount to organizational success and failure, just ask Wade Phillips.
If i was an NFL billionaire owner, i would use every tool at my disposal to try and convince Jim Harbaugh to be my head coach.