Numa,
In your instance the best paying airline (provided you have the appropriate types) is Virgin, followed by Jetstar, followed by Qantas. These are the 3 main players in Australia. Both Virgin and Jetstar have an annualised salary that is the same for all employees regardless of their length of service with the company, with additional payments for extra types. Qantas have a progressive payscale where you will move upwards through the system with time and additional types. Qantas operate the most number of types by far so potentialy you can get more qualifications there than Virgin or Jetstar who both only operate two types. That said, I believe the level of training is quite low at Qantas and selection for training can be subject to nepotism. Some people get everything and others get nothing.
If you had two relevant types you would be on approx:
Virgin - $123,000
Jetstar - $106,000
Qantas - $93,000
These are before tax figures and after tax purely depends on your personal situation with regards to your final tax liabilities, however in Australia they will be high regardless.
Virgin is your best option by a long shot.
GB