I do not like the idea of having Japan need all those territories for an NO. There are so many avenues of attack, it seems hard to imagine Japan getting the NO for more than a round and if they did, then they would be in a position that they would not need it.
I feel it may be a better solution if Japan were to have an NO for Hong Kong (Kwangtung), Manilla (Philippines) and Kiangsu (Beijing). The problem is, those are all victory cities, so wouldn’t Japan already be going for those?
Maybe Alaska would be better, since Japan actually did invade Alaska (Aluetian Islands) historically.