As Qantas has dropped the ball in Japan there must be huge potential to pick up a lot of traffic that has bled off to Korean, China Airlines, Cathay, Thai, Malaysian and Singapore.
A Narita service could also double Virgin Group capacity for London-Sydney traffic.
A Narita service might also provide better a/c utilisation.
QF is now the cheapest carrier on the Australian route ex-Japan, even though the alernatives involve a transit. That goes to show how badly QF has dropped the ball.
Virgin could charge what they liked and still fill the a/c.