Fact 2 : Are any actually available?
That is, the handful of top coaches who are better with a developing team are probably coaching one of those teams.
And some of the better coaches who might be available are better with a veteran team and might not be an improvement with a young team.
Most top coaches are employed, for obvious reasons, so you're either hiring retreads or gambling on a college, AHL or juniors coach.
As far as playing young players, that depends on the player, I don't think playing Sanheim more in the NHL would help his development. That's a judgement call, but each player is different, and a "just throw them in for big minutes" is probably not the optimal development strategy. Some players need to be "sheltered" until they're ready to handle high pressure/tough matchup situations.