We stopped at Rangiroa on the PG and then flew back for 6 nights after the cruise. The Kia Ora has the excursion to the Blue Lagoon. We did not do it as although the weather was gorgeous we were told that out in the lagoon it was too rough. It is supposedly about a 60-90 minute boat ride to the Blue Lagoon. Nov having been there I can't tell you what you would be missing but IMHO I would not sign up for an excursion which would mean a solid 2-3 hours in a small boat potentially bounding around the lagoon.