If you read though the
General Handbook of Instructions, you'll see the youth gets quite a bit of attention and organizational help from the adults. The YSA gets some organizational help, but generally planning and running the events falls on the YSA. When you reach Single Adults (31 and over), the stakes "may" organize a committee.
Even if you were to get though to the leaders and cause the Handbook to be re-written to add your age group, it's unlikely that it would be any different from the current situation where each stake evaluates their needs.
Which is a long way of saying that I would not look to church headquarters to solve the problem. It will have to be done at a local level - and most likely carried out by the very group the activity is intended for.
A starting point may be to organize "a group of us" to go to some community event/activity just to start building some momentum.
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