Our troop really stresses the importance of a Boy Run troop. They are really responsible for everything except money management; even then, they are instructed to find out who paid to alert the treasurer so they know who owes for trips.
Otherwise, the SPL and Green Bar plan all of the meetings. The SPL even organizes special guests such as local fire departments or EMS squads willing to do demos. Trip itineraries are always planned by the Green Bar as well.
In my experience, especially when I was in their position a few years back, the more responsibility a scout is given, the more he will do. The boys are more capable than many think and with added responsibility, they will rise to the occasion.