I found the wave runners and off road adventure on Bora Bora to be superb.
Moorea, a car is a great idea( easy to do alone). If you can swing it, a kayak paddle to an off shore Motu is amazing.
If you are in Moorea when the whales are there, just get in the water any way you can. If you can't see them, you'll hear them.
Just be flexible (hey it's raining, let's have a long lunch!) wear sunscreen and love every minute.
Motu Mahana...words can not explain how perfect this day is. Doesn't matter what you do.
If you dive; Bora Bora and Moorea offer fantastic dives.