Some suggestions from a long time Clays shooter to make the league more attractive to non hardcore shooters. Limit the shoot to two rounds of Trap or Skeet per week or a half round of Sporting Clays(50 birds). This keeps the cost down for less affluent shooters. Do it as early as possible in the morning and no longer than a half day. Ease up on the rules to allow new shooters to get familiar with the game. Example: allow them a re call of the target if they forget to remove the safety, have a jam, or are young shooters just learning.
Do not allow monetary prizes or gambling. Shooting for money brings out the worst in people. Set up classes based on scores using the "Lewis" system. That way everybody has a chance to win. Stay away from the ATA diehards. No shootoffs! Maybe arrange for a barbecue if the range allows but do not require the shooters buy a lunch as part of the shoot. (Some clubs do this, it makes the shoots too expensive for some folks).
Don't laugh at the folks shooting Mossbergs! But teach them to clear jams properly!
Make it fun to be there, not a cutthroat competition. Give out awards like most improved shooter, top junior/lady etc.
Shooting should be fun, and if you make it so the league will succeed.