I will only ask how much is an A320 or B737 worth, how much is an individual life worth, is a Ballina-based secondary radar too expensive, is a single-person ATC Tower too expensive?
Yes, it is too expensive.
CASA, Airservices, ATSB and governments won’t call it for what it is, but that doesn’t change what it is: affordable safety. (There is a twist to the concept in Australia, though: The concept of “affordable” is affected by politics.)
Airlines and their pilots make the decision, all day every day, that the risks of flying in and out of places like Ballina (and Mildura and Wagga and..) are “worth” taking. Nobody is making them take those risks.