I just checked HNL-TPE in December-January...right now they're $375 each way ($750 round-trip) + 68.80 in taxes = Total All In is $818.80.
HA hasn't updated the amount of mileage earned to Taipei just yet, so CPM might be a bit difficult to calculate, unless someone knows it offhand.
https://www.hawaiianairlines.com/haw...ian-miles.aspx
As far as the westbound flight times, 2 a.m. is great and will allow you to sleep all the way to Taipei (you land right around 6-6:15 a.m. the next morning!)