There are over 200 hiking trails on Oahu; which is your favorite? How can we make hiking on Oahu a better experience?

My favorite hike is the Likeke Trail, because of the waterfall at the end. Somehow limiting the number of people per day on each trail, to lessen the crowds, would make it a better experience. Maybe a permit or registration system. Or, a trail access card, although how would it be monitored? Also, more information about safety, caring for the trails and hiking etiquette would be good. –Richard S.