There's only one variation of Suzuka which is not used in GT5, that variation being the "west course" which was seen in GT4. Oh, there's also the motorcycle course which is only slightly different from the ordinary full course.But I would love to see more variation from SUZUKA circuit, There are many turns that are not used, so I would love to set it up manually what to turn on and off.
'Tis the same with Fuji. D1GP use the twisty back section in reverse because of the elevation.Only time I can think of reverse on Suzuka is on D1 drifting, even then it's just the esses section of the track.