I'll be a contrarian and say that if either of you likes windows and doesn't mind climbing over the other, the 789 is a wonderful plane and HND is a great airport. But if you like the idea of all-aisle access and personal space instead, then 1DG on the 77W is the way to go. NRT isn't bad at all if you take either of the fast rail services into the city (N'EX or Keisei).

As a solo traveler, the 77W has the 789 beat by a mile. But for couples, I like the ability to get a window pair.