If you are curious about Anegada, you should go. I think going for a night is fine. You sail in the morning, arrive midday, explore the island for the afternoon, have a great dinner and take off the next morning. You'll leave wanting more which is not a bad thing!

I highly recommend renting scooters, especially with teenagers. They'll have a blast. I think officially they are supposed to be 16 to get one of their own though.

P.S. And just talk to your skipper and don't worry about everyone telling you what you should or shouldn't do or what is or isn't expected.