I'm sure this has been answered before, but a quick search didn't yield anything obvious. Apologies in advance if you think I'm lazy.

I'm about to book a family vacation to Fiji on NZ56 (772) and 57 (77W), and I'm wondering what upgrade options I have as GE (earned from longhauls and domestic flights--I have never flown shorthaul with NZ).

Here are my questions:

1. Is Works Deluxe on these flights automatically PE? Or are they allocated based on status?
2. Can I (and my family) get PE seats on a Seat+Bag fare solely with my GE status?
3. Can I use my shorthaul RU + elite airpoints upgrade to upgrade all three of us to C? I don't really think 500 Airpoints for 3 hours in C is a good way to spend them, but I'd like to know if this is an option.
4. Is Skycouch an option on the 77W on this route? We have a two-year old so it would be perfect.
5. What would be the booking/upgrade scenario with the highest benefit:cost ratio?

Thanks to whoever takes the time to answer them!