Sorry to rain on the parade a little, however the prevalence of good ADF salaries and lack of leavers means the RAAF training "tap" is being turned down a bit at the moment, so it will be harder to secure a position.
That being said, history shows that this is an indicator of an imminent upswing in the aviation industry (ADF actions being delayed over a couple of years), so in a year or so there will likely be strong moves to turn the tap back up again.
Regardless of what happens, just know what you want to do, learn everything you can about it, make good contacts and go for it. No regrets. Cheers.