Our Summer team consists of 8 girls from the same school district. The girls are all friends and still enjoy the summer team experience they have with their friends from school. I cannot tell my daughters that we are no longer playing with their friends.
Fall ball for us has to consist of a team that will take on girls from other teams to help fill out a roster. That is why the question was asked. We are looking to have the opportunity to try out for a team that doesn't require a year long commitment.
If you do not plan on summer showcase events it will limit any of your players exposure to perspective colleges.
All of the colleges interested in my players do like to know a little about the player and their fall/summer schedule and that is where building a player profile comes in handy and the player established with a team.
You will get more bang for you buck if you do not plan on doing summer showcases with just going to college recruiting events like Queen of Diamonds etc or having your players attend a college recruiting camp they are interested in. However, on the application they too usually want to know about the player and the team they are on commitment level etc.
Good luck in your search, there are teams out there you can hook up with for some fall ball.