Changing style/sound for anything other than musical progression = sell out. She should use English only when she deems it necessary, and not for the sake of more widespread acclaim. As much as I'd love her to be famous here in England, if the world can't accept her native language, that's their loss. I have no idea why the Japanese market is ignored when critics and western music fans widely accept the likes of Bjork, Sigur Ros and Rammstein.
And welcome, by the way
You should introduce yourself properly in the
New Members Thread.