I have 3 boys that have played, or are playing on summer teams.
I would rather have someone who has the incentive to put the time in to coach their team properly with their kid on it, than have an outside coach who is only there because he is getting paid. As long as the coach isn't the proverbial frustrated athlete, that is living thru their kid.
Look at the 91 teams that did well last year, all or most of them had a dad as the head or asst. coach.