a huge amount of money and work is required, and I would hate to see it all go to waste.
Don't worry it won't all go to waste. Mayor Kevin and friends will get great personal value from their monument even though there may be no international flights.
Rotorua is a considerable tourist market, although this mainly comes from Asia rather than from Australia
I agree, and the international flights therefore need to be coming from Asia which means bigger, heavier aircraft and the associated infrastructure these aircraft require, which is not just a longer runway. I doubt there is enough potential business to justify such expenditure.