You definitely wouldn't be able to come back via NZ even now if you're not a NZ citizen or PR. If the Australian government announces penalties for using a loophole that would obviously factor into a decision as to whether to travel whilst we wait for borders to reopen. I think they would only think about imposing penalties if there were significant numbers using loopholes that they can't close to leave and then coming home whilst restrictions remain in place taking quarantine spots away from those struggling to get an economy seat on flights.I was having a bit of a think about the potential loopholes. If we were using NZ as the transit to travel to say Europe, one way NZ could restrict that would be to limit the booking of hotel quarantine to NZ residents and PR. So as an Aussie you wouldn't be able to come back that way. You'd need to fly directly back to Australia, and could face penalties from the Aussie government for breaching the BioSecurity Act (if they find a way to do that).
I've never been to NZ and would like to get there someday, but obviously a loophole going via e.g. Singapore would be more convenient.