Hello,
Congratulations on your WP!
Here's my comment on your Q about leaving NZ for a visit back home. I was just reviewing the application to work in New Zealand form which I printed out yesterday. It says here that this form may be used to apply for a visa or permit or both. But you already have a work permit!
To continue, the form has several conditions and you need to tick one which applies to you. I think this might be the one for you should you want to leave NZ while your WP is current:
"I am applying for a work visa. Mark this box if you want to travel to New Zealand to work or if you already have a work permit and want to leave New Zealand and return to continue working."
The downside might be that you need to give time for them to process it before your planned trip and pay another set of fees. But I might be wrong there. Maybe I still need to read more on the Guide for Working in New Zealand which I will do this weekend. Should I stumble on something, I'll share it with you.
I guess its really hard to live with teenage kids. I also have 3 boys and the eldest seems to be not enthusiastic about moving elsewhere... might be because of the girlfriend.
Anyway, am still gathering a lot on info and trying my luck in getting an offer first before I submit my application.