First of all i would recommend doing the trip in C. Considering the lounges, priority check in, extra luggage etc is well worth it. Assuming you credit to M+M this trip will also give you around 50.000 miles then, apply for a credit card and you almost have another business class RT to the US.

Hawaii could be a problem, because yo likely have no 777 HNL-NRT. You could do a LAX-AKL and buy a separate RT to Hawaii which depending n the season can be really inexpensive. This would also leave you with a few miles to play with and potentially add a few more stops (like SIN or BKK or India or China etc).

Instead of LH you could also look at LX for ZRH-SFO (the should have their new fairlt narrow but fullt flat seats).