I am a PPL. I've missed the hoo haa over this since for the last Two months I've been otherwise occupied (building a boat). I would normally fly about one hour of circuits or suchlike a week at YMMB just to keep my hand in, with longer trips once or twice a year.
I have yet to experience the new changes, but I was noticing for at leats the last Eighteen months that circuit conditions were becoming marginal at YMMB on occasions. This usually occurred when there were 6+ students in the YMMB circuit, of whom perhaps Two or Three were "wandering all over the sky" like we all did when we started. Add to that inbound aircraft from GMH and Academy (for the eastern strip), perhaps requesting circuits on arrival, and things became busy enough to hear a little stress in a controllers voice ("Waggle your wings, which one are you?", etc.).
At that point I usually ended my own practice and got out of the way.
I will try the new system shortly. I fail to understand the clearance requirement for inactive strips, and I think instructions to land for a full stop in the event of incoming aircraft (if these are actually given) are bizarre.
If they interfere with my flying, I will go somewhere else, or out of the activity altogether. I think others will too. Melbourne has/had what would be almost perfect GA facilities if YPCK, YMEN and YMMB were used as they should be, but that is never going to happen thanks to a brain dead tstate Government, property developers and of course our dear friends in Canberra.