For Japan, NWA is limited by capacity controls (NRT has only one runway that can handle jumbo aircraft) and exceptionally high landing fees. I don't know why there are slot restrictions on the shorter runway at NRT that's used for the smaller aircraft NWA uses (right now it 3 757's...).

If they could fly additional narrowbody aircraft from the smaller NRT runway instead of parking them in the desert, NWA could add a few new compelling destinations & routes within Asia (Kuala Lumpur again? Ho Chi Minh city?).