The replacment of the RAAF, FA-18's and F111 will depend on which side of politics is in power.
A Liberal government would probably spend the dollars required to ensure an effective combat capability and wear a higher defence budget.
A Labour government would be less inclined to commit to a higher defence budget.
So Liberal government = maintaining combat effectivness
Labour government = Budget bargin time.
We just have to look at the decisions made by the previous Labour Government on Defence.
Rust bucket ships purchased from the USA
Frigates unable to effectively defend themselves.
Submarines, just spend another couple of billion dollars and they might then 50% effective.
I don't hold much hope of the RAAF being able to maintain an effective combat capability in the future the cost of modern generation fighters and the lack of any real threat, may see the RAAF go the way of the RNZAF a name and nothing else substantial.