My information is out of date but years ago when I flew transpac, Mileage Plus was the advantage that United had over ANA. I tolerated a lot of crummy UA flights in the pursuit of 1K status, upgrade passes, and lifetime status.

If the OP cares about such things, it would be worth doing a detailed comparison of the various *A mileage programs. For someone flying not-so-frequently, Asiana's program might offer the best chance of attaining premium status with its 24 month window. If the OP is doing frequent transpac flights, they should be able to reach status with ANA or United but unless I am mistaken, both ANA and UA require a minimum number of flights on their equipment to qualify for status.

As for HND vs. NRT, it's funny people used to moan about NRT being sooo inconvenient. With the 40 minute train to Ueno, I don't mind it at all. Mind you, Ueno is a convenient jumping off point for me. For folks in other parts of Tokyo, it's less convenient.