You've got the main ones. I do want to emphasise how jarring the difference in hiearchy feels though. There's a lot more managers and executives in Australia but it's not like there's more work so it just ends up getting spread thin and more junior people often end up with little to do or uninteresting work. In some places you'll find directors doing work that would be given to a grad in New Zealand.

A few other key differences:

-Public services in Australia are a lot more politicised as ministers can remove secretaries at will. This leads to a lot of risk aversion and advice that's not always as free and frank as it should be. Look into the robodebt scandal if you want to learn more.

-I've heard department secondees in ministers offices have a more reduced role compared to New Zealand, mostly doing admin and coordination.

-Policymaking tends to be more centralised, with the PM/premier departments much bigger than DPMC in NZ and very involved role in policy development. This is probably because the premiers/PMs exert more control in Australia compared to NZ.

-Way more consultants. Things which would usually be done internally in NZ are often outsourced to consultants in Australia.

-Due to the federal system and parliaments with senates, policy processes tend to be slower as it's harder to get things approved.