I wouldn't worry about the track detail. We've seen the Tokyo track in a previous demo and that track looked much better. Whats important is that it is running in 1080p at 60FPS.
I do agree with you on the music. Just horrible!! Also, some of the sound effects are still left over from the first GT.
But for any GT game I usually turn off the music so I can enjoy the sounds of the moter reving to redline.