Right now there is a no adv purchase deal from CLD and SAN to HNL for $320 RT and OGG for $318 RT. You can connect in LAX and SFO out of CLD for more miles (around 7K RT), but only in LAX or SFO (not both) out of SAN (around 6K RT). You can do a turn around overnight if you don't want to linger. Do you have any UA elite status? The last flights out of LAX and the last flights back to LAX from both HNL and OGG are somewhat easy to score an upgrade. A little harder out of SFO.