I've done the following DONE3's out of NRT or ICN (each connecting with a DAS13 to/from Australia):
nrt-sin-hkg-jfk-dfw-ord-mco-dfw-sea-jfk-cdg-hel-lhr-dxb-lhr-hkg-nrt 41892 mi
icn-nrt-dfw-anc-dfw-atl-ord-sfo-jfk-fco-mad-lhr-dxb-lhr-sin-hnd-gmp 42574 mi
icn-hkg-jfk-mia-sea-ord-lax-iah-ord-amm-mad-lhr-dxb-lhr-sin-hnd-gmp 45851 mi
These were the most miles I could get out of it with what was available at the time while still stopping when/where I needed.
I'm planning my trip for this year...
The main problem with HNL, and the reason I haven't been to Hawaii yet, is that once you get there, you have no choice but to continue on. No matter where you came from into HI, you can't go back. Being able to do something like DFW-HNL-LAX would be nice.
- I think more could be done in Europe in the winter when HEL-DXB is running, by using S7 DXB-OVB-FRA
I've looked at doing things like that, however the AY HEL-DXB is best avoided for as long as they use a charter fit out 757 and the S7 DXB-OVB flights are really annoying to get booked as it seems to start and stop at the whim of the Russian government.