We loved the PG and the cruise and we did it as a B2B. However, I always said that I wish the Mariner or Voyager would do Polynesia.
We loved having 14 days in FP, but found that a B2B was not perfect...a continuous 10-14 day cruise is more ideal. Very few folks stayed on for week 2 and it was like beginning again instead of building on new relationships. It was a bit sad.
I think you would love the PG, but, personally, I would opt for the Mariner cruise. The PG is just an ok ship compared to the Mariner. It is less a "cruise ship" and more of a floating hotel. We have only positive things to say about the food, excursions and entertainment on the PG, though.
How lucky you are to have this type of problem!!