1–What percentage of those openings are created by the bottom two or three girls on the roster having quit or gone to weaker teams due to a perceived lack of playing time?
Probably about 25% I would say.
There is a good portion where the team is already so weak that some random girl from another team probably makes them better.
Some teams never had more than 9 or 10, so a couple more are needed.
Some lost girls because the coach is a nutjob or the parents were sick of other parents.
Another portion where some parent group breaks off half the team to form their own team.
Some where the best players left just left for a better team or org.
Some players just quit the game
And so on... The reasons players leave are numerous.
Yep, our org picks up girls ALL the time across our org. I would say a good 75% of the local and sometimes not so local 'we have issues with our past team' turn up at our tryouts. Do we take them all? No of course not, but our coaches pick up a whole lot of them; and yes we have 2nd level teams in most age groups - but they all have good coaches associated with them so if they do see something in the girl; they are given a pretty good chance to show it was the past team and not them.2–Has anyone actually had success in appealing to players who felt they were not treated fairly on their last team? I would tend to think this approach attracts more problems than solutions but perhaps some diamonds in the rough.
The other thing is that the community is small. Once you have played a season or two, you know who the problem players/families are. If you take them on, you know what you are going to get. We don't see our coaches take on many known big problems.