Mother Nature can be quite a pervert, can't she? 
Oof. I got some data on my flight to Auckland in a few weeks. 13 hours to get there from Los Angeles. That's gonna be a fun trip. 
Try flying Qantas' 16 hour nonstop from Dallas - Brisbane. Unless you can get a business class ticket, coach will be brutal. :/
Well, coach on Qantas is probably better than coach on American. In fact, I think coach on ANY airline is better than coach on American.
That's funny you mentioned American because Qantas recently launched the DFW route in order to feed connections on AA flights (they have a partnership with American) through its largest hub. I would fly from Dallas to Australia because it seems like such an unusual and interesting route, plus Australia has always been one of the countries I've long desired to visit. Their coach product is decent, but for a long flight, I would opt for their Premium Economy option which is essentially a "first class- economy" product, if that makes any sense.
Also LAX - AKL is a long route, no doubt about it but there are dozens of longer routes from USA. Some of them are:
Singapore Airlines: LAX/EWR - SIN 18hrs
Qantas: DFW - BNE - SYD/SYD - DFW 16hrs
Emirates: LAX/IAH/SFO - DXB 16 hours
Delta: ATL - JNB ~17hrs
United: ORD/EWR - HKG 15 hours
Delta: DTW - HKG 15 hours
United: EWR - DEL/BOM 16 hours
Air India: EWR - BOM and JFK/ORD - DEL 15hrs from New York, 16 hours from Chicago
Qatar Airways: IAH - DOH 15hr45 min
South African: JFK - JNB 16 hours
Thai Airways: LAX - BKK 17hrs.
Hopefully I didn't mean to scare you, Mac
but just try to make the best of it on your flight. New Zealand sounds fascinating, I would love to go there, too, lucky you.
