Air Pacific (the Fiji airline) is an option if you plan to use an AAll partners award. They fly LAX-NAN (three or four times weekly) or HNL-NAN (but good luck finding availability on this one, I think it only operates twice/weekly at most). Their Biz class is not as fancy as QF or TN, but Fiji is a great destination, and has possibly one of the most fascinating cultural mix you're likely to find in the Pacific. The diving, snorkelling, and birdwatching are excellent too.

You'll need to leave the Nadi area, though, preferably for one of the smaller islands around Viti Levu (there are lots: the Mamanucas and Yasawas groups are mostly within a couple of hours boat ride of Nadi-Lautoka). Something I really like about Fiji is that it offers decent options at moderate prices, i.e., you don't have to blow your children's inheritance to spend a wonderful week on one of those delightful island resorts.