@Sammy:
Did the travel ball teams that your DD played on have the same players sitting over and over, to the tune of playing only in pool games and maybe as few as 10-20% of total innings? Did those players and their families happily accept those roles? If so, I think you were very lucky.
The org. my DD played for traditionally had 2 teams in each age group. There were no odd age groups. For instance, at 14u there was the "older" second year team, composed of all 14 yr. olds, then the "younger" team, primarily 13u. Both played 14u in tournaments, so each team had two years eligibility at each age level.
As I recall from 12u on, 12 was the magic roster number including 2 pitchers. Three players were rotated in and out of the lineup according to the team's needs every weekend. Those needs included rest for the starting nine, injuries, etc. But I distinctly remember the coach making it VERY clear that when accepting the roster spot, ALL playing time was based exclusively on that criteria. And those decisions were made exclusively by the coaching staff, period. All the families respected the coach for being very direct and fair. I think that was the glue that made the team a cohesive unit - everyone knew exactly where they stood.
The team's goals were to play as late as possible every Sunday, so as to face the toughest competition and be challenged as a team. That was OUR goal for our DD, and the team's goals matched that - especially when they reached 16u playing in showcases.
I have the mindset that player development at 12u and above is done primarily in a private setting, and team practices are for TEAM development and working on team oriented things - NOT primarily for hitting, pitching or fielding fundamentals. Basically... practice at home. There is just too much to do in a team practice to develop a competitive team, and trying to teach a 12u and above how to throw, pitch, hit and do fundamental fielding in a team practice wastes valuable team practice time. I have always compared this to an orchestra. If a french horn player doesn't know her part (hasn't practiced on her own), rehearsal ISN'T the time to learn it. Therefore, the whole group suffers until she DOES get better.
At 10u, it's a little different scenario, but I think the goal should still be team development based on individual fundamental development. New parents at 10u might rely on the team coach to do everything, thinking this is all they ever need. This is the year that parents need to learn that to succeed, their DD must work outside of games and practices - on their own - to become a better player and win a starting field position. So at 10u, the weaning process starts, and you weed out the kids/families that find out that it is going to take far more time commitment that they are willing to give. Otherwise, at 12u, the entitlement mentality will become a big headache for the whole team.
In a competitive environment, when you put entitlement (for any reason) in the same sentence as team/player development, you open a big can of worms. IMO, at 12u and above, if a kid isn't getting the playing time they THINK they deserve, it may be a sign they are on the wrong team.