I hear actuaries get the big bucks, but i have a friend who use to be one but became a maths teacher instead because apparently they work you like dogs, can call u to come to the office whenever they want, which is part of the reason why the salary is so high, i would recomenend mining engineering, they have good salaries, but i think you end up in the middle of SA/NT for a 2 weeks and back home for one.
Meh anyways, i think salary plays an important role in choosing what u wanna do, but if you have NO interest in that field, you will hate your life.