I agree with prior posts, I would add that when it comes to experience, I take note of coaches who have coached at a college or pro level. Playing experience at those levels is great (and a plus), but I think someone who has been paid by a college or pro team to coach may understand how college coaches think. Plus, it is good learning experience for the players to play for someone who is familiar with how things work at those levels.
Decent organizational skills really help, or a support structure to provide those. You may be the best baseball mind in the world, but if you can't get the team registered to play, nothing else matters. My son lost a summer playing for a good baseball guy who only got the team into 3 tournaments.