The two things that killed the QF service between AKL & LAX was the change of the NZ domestic feeder services from the Jet Connect flown Qantas operation to a Jetstar operation and the change of aircraft from B747 to A330 - the slower cruise speed and the requirement to fly a longer route (to meet ETOPS) meant that the elapsed time was significantly inferior to the Air NZ services. The AA B787-8 service will solve the elapsed time issue but it will be interesting if customers will accept the JQ feeder services.
The A330 has 180 Minute ETOPS and did not need to divert on this route. The most probable reason the A330 was pulled was to defend the 65% "line-in-the-sand" domestically.