I think you would get a great deal of enjoyment out of New Zealand.

To be completely honest, it will be touristy just about everywhere you go in the times you're looking at coming, as a lot of Kiwis take their Summer / Christmas break anytime between December and March.

I would recommend that you visit both the North and South Islands - there's just so much to see, and you could take your time doing it if you were to book a campervan (Google 'campervan hire NZ' - there isn't a consolidated website gathering the best deals, unfortunately, so you will have to get individual prices). There are heaps of places you can park up and stay ... the campervan providers will have all the details.

If New Zealand is what you decide on, I'd recommend you fly into Auckland, travel North to see the sights up there, then travel back down the North Island and then do the South Island. If you love wineries then you should travel down the East side of the North Island through Hawkes Bay; but if you want mountains and adventure then you should travel down the West side through New Plymouth ... or otherwise straight down the middle, through the Desert Road (the most common route). Rotorua - just above the centre of the middle of the North Island - is extremely rich in culture and a real tourist mecca (in a good way!). Robin Williams (the recently deceased comedian), used to travel to Rotorua regularly to cycle around the lakes.

Wellington is often referred to as the 'coolest little Capital' for very good reason - not only does it have the most incredible range of cafes, nightlife and entertainment, but you could easily stay here for a couple of days and visit places like Parliament Buildings and the Beehive, ride in the cable car, and see the seals at red rocks ... there is just so much to do. (You could even venture over the hill to the Wairarapa to visit the world acclaimed wineries over there, and visit the beautiful coastline where you might be lucky enough to see a seal or two on the rugged beaches [James Cameron, the famous film Director, lives out that way]).

The temperature in New Zealand during Summer is a very tolerable 25-35 Degrees Celsius - 28/30 being the average (much cooler than Australia). And unlike Australia, we don't have snakes or crocodies!! ;-) Australia is very beautiful too, but I think based on what you've said, New Zealand would be able to tick most of your boxes for a very memorable honeymoon.

If you decide on New Zealand and would like some recommendations on things to do and places to stay (if you want to go down the hotel / resort route), don't hesitate to ask :-)