It's a cool idea. I think it's the logistics that will hurt you.

Your plan requires basing an airline at Totegegie Airport. Take a look at where that is... it is an island it itself. You'd need pilots and mechanics and spare parts there. Honestly to ensure reliability you'd need a second aircraft. Obviously your main operation would be in Mangareva but that's still a very remote Pacific Island with 1200 people. Not an easy place to run an airline from.