Have done this trip numerous times with groups of kids in this age range and always a blast. I will say that the adults don't hold back and still have plenty of fun (and painkillers) as well. We'll be there in May/June with five 14-17 year olds. Some other ideas not on your list:

Snorkeling: Cistern Point (Cooper), Monkey Point, Diamond Reef (at Marina Cay), Loblolly in Anegada (Flash of Beauty to Big Bamboo)
Scrub Island is a good break for kids to play in pool, hit beach toys, snorkel at Diamond Reef, Hike, and give adults a little time away.
Michael Beans a Leverick is fun to get into and get kids in Pirate attire (maybe gone by then?)
Surfing on Paddle Boards behind dinghy (carefully and not in mooring field)
White Bay is still a favorite - after a long day on the beach (and bars), we always get Pizza to go at Coco Loco or Corsairs for a relaxing night.
Love the Norman Hike
Always fun jumping off Willy T as long as it is earlier and not too wild.
As said, Moke's are fun in Anegada, and/or rent a safari truck for the day and pack them in the back. See the Flamingos, drive to Loblolly, then back to Cow Wreck and ABC on the back roads.
The kids always love dancing at Potters with Sam. We love it, but also have split up and gone to Wonkey Dog while they eat there.