Bob -
Re: NZ - I highly suggest that you use the small planes to get around the North Island if time is at all a concern. From Auckland, take the short hop to Kerikeri and then drive the 20 minutes to Kauri Cliffs. Especially since you are with your wife, you should stay at least 1 day at the Lodge there at Kauri Cliffs. It is one of the best little hotel experiences in the world. Great rooms, GREAT food, and the Robertsons are wonderful hosts. Their son Jay is actually the GM there. Make sure to time it so you can experience one of the picnics that they do for the guests at their beach. They golf is good and they have just opened a new spa. You'll meet people from all over the world who come to stay there regardless of the golf, and everyone eats together in the dining room at night. Also, try to have them arrange a visit to the Kauri Trees at the top of the North Island. Use a helicopter if you can.
From there, drive back to Kerikeri, puddle jump back to Auckland, change planes and fly to Napier. From there, drive 30 minutes to Cape Kidnappers. I don't think that the lodge is finished yet, but there are some decent places to stay in Napier and Havelock North.
After that, you should try to go to Wellington for Paraparamu. Then find your way back to Auckland or go to the South Island for sightseeing.
One last thing, if you are willing to take a side trip from Sydney, you better take the 2 hour flight to Launceston, drive the hour to Bridport and stay and play at Barnbougle. Not expensive and maybe the best course built since Sand Hills.
You didn't mention Melbourne, but the Sandbelt is obviously a must at some point in time.
Have fun and let me know if you need some other hotel ideas.
Michael.