Travel itinerary ideas for north-island (NZ)?

I've got until the 2nd of April here in New Zealand which means about
2 weeks. Right now I'm in Christchurch, will move on to Kaikoura
tomorrow, Picton and Wellington the next day. I'll probably stay in
Wellington for a couple of days before taking on the rest of the
north-island, but at the moment I don't really know too much about
which places are worth seeing.

I've had a few suggestions here, but I'm still pretty confused, so
I've been reading a bit and have come up with the following which I
probably have to pick and choose between:

- Rotorua (Maori culture, geysirs, mud pools to soak in, sheep
sheering)
- Taupo (thermal pools to soak in, beautiful lake)
- Waitomo (glow-worms, limestone caves)
- Coromandel (natural spa baths)
- Tongarino national park (smoking volcano: Mt. Ruapehu, volcanic
landscape)
- Napier (art deco type city)
- Palmerston north (not touristy, relaxing university town)
- Tauranga (Kiwifruit growing)


1) My final destination will be Auckland where I plan to spend a few
days to wind down before I move on to Japan, so is it easy to get from
Coromandel to Auckland, or is this a long detour? Natural spa baths
sounds nice and relaxing.

2) As I haven't been to any of these places before, are there places
mention here which are repeats of the same things I'll see other
places? I'd rather not waste time seeing the same thing twice in this
limited time if I can go to some other place and see something new.
I have for example seen glow-worms (in the Fox glacier township), so
I'm not really bothered seeing it again in Waitomo, even though
they're in caves, but then again I hear that Waitomo is worth stopping
by because of the unique caves...

3) I don't intend to spend lots of money on tours etc. (remember,
Japan is next, so I really need to save up!). I'm more into just
hanging out, soaking up the atmosphere of a place, taking small walks
on my own etc. than joining some expensive organized thing. Can I for
example visit some of those caves in Waitomo myself without having to
pay a lot for joining a tour?

4) What exactly is "Art deco"? Napier is supposed to be an art deco
styled city, but I don't really know what this is and if it's so good
that it's worth stopping by.


Hallvard