Wait till you're 85 then you can move to NZ and be a youngster again
I think the two countries are very different. There's basically bugger all in NZ, even the cities, apart from Auckland, are really small.
There's 1m people on the south island, 400,000 of those in Christchurch, and a couple of hundred thousand spread over Nelson and Dunedin, then pretty much nothing anywhere else. It's a great place to be antisocial! But stunningly beautiful and a cool place to be if you like the great outdoors.
FWIW, if you are planning a trip accross the ditch, and plan to head south, winter is probably the best time, the scenery gets miles better once there is snow on it, and the weather is usually pretty good. Bloody cold if you intend to surf though.