Except they have not replaced the DGA approaches in any meaningful sense... Flinder Is is an excellent example. Perhaps that's an isolated example.
That depends on how far they go with the rationalisation. I can think of at least 5 airports off the top of my head around Australia that if your only option was to fly runway aligned approach from 10 NM it will add significant track miles (ie 30NM) to the majority of arrivals. According to the AIP SUP though they don't plan to close any more additional aids in the near future.
I would assume CASA are hoping that the airlines pony up for RNP approaches (which has already happened) and everybody else will just have to pay for the additional fuel burn.