We are in the early planning phase of a 25th anniversary adventure, mostly to New Zealand next March/April. We only have 14 days, coming from upstate New York. Our plan will be to drive ourselves around (fly as needed) and stay in hotels or airbnb. While I'd like to say we may return some day, this is a trip of a lifetime and a return any time soon is unlikely. I could easily plan a 30 day trip, but with only 14 days, I don't know what to cut out!

Should we spend a couple of days in Sydney, then spread 11-12 days across north island and south island? Or should we skip Sydney and north island and immerse ourselves in the south island the entire time? Which of the following would you say are "must see?"

We will both be 50 years old and in decent physical shape. We like hiking and adventure, although no bungee or hikes longer than 6-8 hours.

Auckland
Rotorua
Wellington
Abel Tansman
Franz Josef Glaciers
Christchurch
Queenstown
Te Anau and Milford Sound - already on must see list
Kaikoura

Thank you for any advice to get me going.

Or should we skip Sydney and north island and immerse ourselves in the south island the entire time?

This!

You barely have enough time to explore one island, let alone three (counting the big one of Australia).

Definitely don't try to do Australia and NZ in 14 days - do one or the other. You can do a quick trip in both islands of New Zealand in 14 days but that won't allow you time to relax and really enjoy the scenery. Better to concentrate on one island - both north and south islands are beautiful in different ways.

They already said it. Focus on one island. And yeah, skip Sydney and North Island so you can focus the enjoyment and relaxation on your 14days tour. Minimize it so you will not be stressed out running with time. Happy anniversary to you couples! Enjoy Aussie!

Thank you all. We have decided to stay on the South Island for the entire 2 weeks!

Woo-hoo! I think you'll be happy with your decision!

Just be mindful of school holidays:
https://www.govt.nz/browse/education...-and-holidays/

I just noticed you have two posts on this forum and that Melnq8 already advised you of the school holidays in your other post.

woah! Thankyou