Charlie
For Bushwalking, I’d recommend Kakadu national park near Darwin. They’re doing a great job of protecting it - a good perspective on the aboriginal people (I won’t delve into the other perspectives - too political).
We took a 3 day tour, with some hard walking, yet often with the reward of a fresh (and I mean fresh) waterfall and lake at the end of it.
Darwin is a funny place, by reputation a place people go when they’d rather not be found. I found it relaxed & easy-going - a pleasant backwater. However it was the only place that seemed to retain a coldness to Japanese tourists - a legacy of the bombing of their harbour that seems to be ingrained in the local consciousness.
This is a good option if you want a counterpoint to (say) Sydney.
If heading to Sydney, then a trip to the blue mountains allows for some good hiking, as easy or as hard as you want it to be, encounters with Kangaroos, and well-maintained trails. Hunter Valley is in easy enough range, and you can always stop at ‘Summer Bay’ (Palm beach) en-route. I rather embarrassingly had a sudden feeling of deja vu when walking along the beach, only to then realise I was remembering the opening sequence from Home & Away.
Personally I prefer Melbourne, having lots of personality, whereas Sydney is the big and slightly brash metropolis. Not a fan of Perth or Brisvegas (err I mean Brisbane). Adelaide sounds lovely - and an obvious choice for wine. Melbourne however is also very easy for wine, not just the Yarra Valley, but a small handful of very good wineries near the airport (tullamarine?) e.g Craiglee.
As for NZ, Wellington has emerged from dull functionality (or so the brains of the operation advises) into having a vibrant scene and arguably at the very peak of coffee brewing. A local UK barista reckons they are streets ahead of Italy now, and it was indeed impossible for us to find a poor cup of coffee, indeed it was impossible for us to find one that was even worse than excellent. Martinborough is in range, but with a surprisingly taxing trip over the hills to gets there.
Auckland would appeal to many, and there are good wineries on it’s doorstep.
For me the most interesting wine region is Hawkes Bay, and the advantage of this is the ‘art nouveau’ city of Napier. Quite an amazing place to walk around, with thermal waters as well if that interests.
No comment on the South Island as I’ve not been there. They say it’s more beautiful than the North Island, but that would wrongly imply that the North Island isn’t stunning - it van be breath-taking in its own right.
regards
Ian
p.s. I do recall people a couple of decades ago, who firmly maintained the reefs off Western Australia were in much better shape than the Barrier reef. Things might have changed since.