Free or heavily discounted medical for civilians is slightly complicated but still better than the NHS. Theres a medicare-surcharge to cover it. Defence members are exempt but if your dependants don’t earn enough annually you may get a reduced tax refund as some will be clawed back by ATO to cover your partners med contributions liability. Aus citizens are encouraged to take out private health cover on top, in doing so their levi is reduced.

Some tips:

• If you are posted to Darwin, dependants registered with veterans medical group near the CBD will get 100% back every time through adffamilyhealth.com and their medicare-rebate even if they used their $800 annual allowance. (not including prescriptions)
• The use of bulk-billing facilities in all states can work out to be free
• Dental tourism is becoming popular, you can go to Bali for 7+ days, stay in a 5 star hotel on the beach. While there get treatment. The total cost including treatment, flights, accommodation, food and drink can be less than it would just getting the same 1-3 hour treatment in Melbourne, Sydney or Brisbane. (Maybe use an RLLT for a holiday and get treatments while there)
• Defence health and navy health offer defence family discounted policies on private cover. There is usually a rep at the new Lateral welcome days
• canstar.com.au/health-insurance is a helpful comparison site

I hear if you plan to have children in Australia, it pays dividend to have private cover to ensure the best treatment and private room post labour.

Warning! I have also heard more than one tale of private health not delivering the right or agreed cover for dental. Often charging for it in peoples 1^st few years of policy, then stating it is not effective until 2^nd or 3^rd year when a claim is made.  Read the fine print!