I did this a few years ago. YOW-YYZ-LAX-PPT (this last leg on Air Tahiti Nui). Then an overnight in PPT until early morning, when we took Air Tahiti to BOB.
Air Tahiti Nui was pretty brutal for a tall person, but I know they're in the process of replacing their A340s.
We went in November and there was some sort of big canoe race between the islands. Air Tahiti check-in took forever due to the amount of stuff people were checking.
Word of advice, if staying overnight, don't stay at the Tahiti Airport Motel. It's right next to the airport but I wouldn't advise walking there!