I with Andy, always liked diamond stitched leather, when I first saw it I though it was a GS that had had its Tech cloth replaced, but its probably a factory extra.
Anyway, red, Its a great colour on the GS, I dont see what the issue is, other than it comes across a little like trying to be a Ferrari, but red works on any Italian car IMHO.
Buy Dicky's GS sills off him slap them on and you have a nice looking car for not a lot of cash. If you hate the seats, you could swap them on here I recon someone will bite your arm off.