Had to jump in on this one.
I know it is the other way round to most people’s thinking but Korean Air via Seoul.
Great product and great airport to change, avoids the US and is only GBP 2430.
Downside, slightly longer journey and you have to overnight in Seoul on the way back but they will put you up in a lovely hotel with transfers and meals.
London 19:35 – 14:25+1 Seoul (lovely lounge) 20:20+1 – Hawaii 09:50+1 (total journey time 25:15)
Hawaii 14:20 – 19:20+1 Seoul (comp overnight) 13:10+2 – London 16:20+2