Canon law actually says Confirmation should occur at 7. The reason given for delaying it for nearly a decade is that it is assumed that withholding a Sacrament is the only way to get kids to show up for catechism classes at all. If the homeschool association could satisfy the bishop that the kids would in fact get a religious education throughout their minority, he would have no reason to withhold the Sacrament, and ought to give it by law.

Separate groups like the lay Dominicans, lay Franciscans, men's group, women's group? I've heard of parishes with adult catechesis where people separate according to which class they want or which teacher they like. Separate groups are a staple in most parishes, and they don't cause problems. Lack of charity does.