Hey, Sierra Juliette! I don't do PPT. but have friends that do... for Hawaiian and Air Tahiti Nui. Both tell me that there aren't any real seasonal peaks exept for around mid-December. They estimated loads at about 87%, all classes, especially business. TN does 4 flight daily but Hawaiian goes to Honolulu first... no non-stop. I guess the only other operator with non-stop is Air France... don't know much about them...
Everyone comments on the great service on the aging Tahiti Nui A-340's, with the execption of the LAX departure where the pax are still bussed to the departure terminal. (Before departure at LAX the FA's change into the Tahitian Pareos... nice touch)
Both the guys said that riding a pass shouldn't be a problem, (if that's what you're planning) but mid-week tends to be the best... both ways. (about 8.4 hours on TN).
Sorry I couldn't be more help...
Enjoy! (Let me know how it goes)