Indeed, you could blow the whole lot by doing 5 nights at the Sheraton Moorea, 5 nights at Bora Bora Nui, with an overnight at the Sheraton Tahiti by the airport in each direction.

May not be the best as far as getting the most per point -- and you haven't shared your definition of luxury -- but it's certainly one idea to investigate.

Another would be to bounce around... Hotel Danieli in Venice, the St. Regis in Rome, maybe pop over to the Hotel Grande Bretagne in Athens...

Depends on what rings your bell, really.