The type of licence you have depends on your flying needs. If you wish to take more than one passenger, PPL it is. If you want to fly at night, PPL it is. If you wish to fly for a living, CPL it is.
If you want to go in CTA PPL it is. If RAAus wants to be in the CTA then they will have to apply the standards and regulations across training, currency and maintenance which would surely close much of the price gap that you guys cherish.
I have a go-kart license doesn't mean I am allowed on the roads although most of the skills are the same!