Qatar from Oslo is usually the best value, sometimes Stockholm.

If the timings work better, you can sometimes fly to Sydney for one leg (certainly to/from Wellington, as I've done that on the way home). Timings actually look pretty good all the way to AKL - basically go to OSL late the night before, sleep late, get the late afternoon flight to DOH and then stay awake until around 5 a.m. EU time before (trying to sleep) for 10 hours or so.

This March, it's £2.5k + 600TP although Air China will do it for £1700.