Safety culture. Safe and sensible flying is encouraged and an ethos which emphasizes that the PPL is only the beginning. Opportunities for group fly outs to far flung places or just brush up lessons. Maybe a free lesson (only the instructor, not the aircraft) every 10-20 hours of flying or a mandatory one every six months. To do the fun stuff and things people forget (stalling, crosswind landings, PFLs) it can be made very good fun.