Dena -
Do not book anything the day of the Motu - it was so wonderful. I had a spa appointment and regretted that I had made it for the Motu day and I left early for it. It was a great treament (Body Scrub and Massage with sunflower seed paste!) Don't forget to bring a blow up float for the motu.
My favorite two excursions were the Aqua Safari and the Photo Excursion on Moorea and third was the Lagoonarium on Bora Bora. The Lagoonarium included a canoe (motorized) ride completely around the island. Heaven!!!