ok I'll bite
Whilst NZ does have some breath taking scenary (I should know my wife's a kiwi and we've been just about every year for the past 5!!!) NZ is so......Europe and North America. The beeches and the pines, the glaciers and mountains are wonderful but they are familiar.
Australia on the other hand, deep red outback sands, snow white beaches, turqoise waters, mysterious rainforests (with more than just gum trees I might add

) Wetlands as far as the eye can see with an amazing array of birdlife, termite cities, the second longest mountain range in the world (not very high but very long!!!).. I could go on
Granted you will have to travel thousands of kilometres but that means thousands of photo opportunities
Also at least the weather will rarely let you down.
I went to Milford Sound last time and they told me they were in a drought...because it hadn't rained in 7 days!!!!!!!!!!!
At one point it didn't rain in Sydney for 7 months, great for tourists bad for locals.
Steve Parish and Ken Duncan have made a killing photographing the Australian landscape.
I await my kiwi cuz's response