Ned
I know youre a great photographer and youve certainly seen alot of operators around the world but i can tell you that working for some of those companies on your list and going flying to do publicity shots for them are very different experiences.
Unfortunately theres a few nz companies exploiting young pilots and you really need to ask guys that have worked there before you recommend operators.
There are very few i would work for.
The thing i tell everyone is to get a working holiday visa in canada once you get a few hours (you have to be under 30yr old). Its a much better industry with real pay rates and everybody i knew had a comfortable standard of living.