Pilotchute/featherweight
I was aware there were concession for the exams for ATP conversions, I did think that Airlaw was the one you had to do. However I understand Qantas group, and perhaps others, still require all exams to be completed. I did FAA CPL to CASA CPL years ago and from memory it was only Air law exam for that.
That still leaves you with the instrument rating which can be challenging for anyone who hasn't flown in Australia, hasn't flown a duchess (or whatever) for who knows how long and who may never have flown NDB approaches. That is of course unless you can find an employer willing to assist with all that.
A lot of discussion here about Medicare and cost of living etc but for the average non Australian pilot I would think the time, expense and effort to convert from FAA certificates to CASA would be the thing to look at after figuring out the visa.