I haven't played around with the NZ website, but believe NZ40 flies 2x weekly, AKL-PPT.
TN flies the route 3x weekly.
But if you're looking for "great resort with excellent snorkling right on the beach" then you do not want to simply fly to PPT. The island of Tahiti is not what once envisions when thinking about French Polynesia. Certainly teh intercontinental on the island is a lovely resort, and has overwater bungalows, the what you really think of is Bora Bora -- which requires an extra flight on the domestic Air Tahiti (VT), PPT-BOB-PPT runs ~ US$380 roundtrip usually.
Moorea probably has better snorkling than Bora Bora, though is a bit less stunning in terms of scenery.
French Polynesia is also a pretty pricey destination, they're in the middle of the Pacific and most things have to be shipped in great distances.