OK then McLimit if you want the full US system in Australia then we are on the same side. I hesitate to say "Me too" in the present environment.
No, we do not need any local "improvements" on the US system - they have never yet been genuine improvements.
No re-inventing the wheel and making it a triangle as so often happens here.
My only reservation is that any aircraft equipment has to be not only US but also ICAO compliant.
So the US 978 MHZ transponder would not work here - we can only use the common US/ICAO 1020 MHz unit.
And to be clear; don't just give the airspace the same name - use it in precisely the same way - ATC and Pilots.