Use UA miles:
Hawaii-->Oceana, although LOTS of flying.
OGG-->HNL-->NRT-->AKL-->PPT (25K Econ/40KBiz)
OGG-HNL on HA
HNL-NRT on UA/All Nippon/Asiana
NRT-AKL on NZ
AKL-PPT on NZ
AKL-PPT usually never opens J class on NZ though.
RT bookings can include a stopover in AKL or NRT for free.
Hope that helps.