Usually, the weather is no good in winter in NZ. It seems that your trip is mainly in north island. The weather is mostly fine in spring and summer.
Next time, go to Lake Tekapo in south island around spring and early summer. It's the best place to watch stars. The chance of clear sky is better than anywhere in NZ. There's a lot of accomodation here. It's also a nice place to stroll around. A national observatory is set up on the mountaintop nearby.
Anyway, it's a great time for you to relax and enjoy the "green side" of NZ
Next time, may be we organize a group to have a star trip there.
Enclosed are images from Lake Tekapo |