I must admit, I wouldn't mind being rid of the catalytic converted just to get rid of an incredible source of heat near a) my right foot, and b) right under the shock.
I think a well-designed cat-less full exhaust would probably be the best solution. I wouldn't mind a lighter exhaust and a little throatier sound, but only a little. It would also be nice if one could tune the 5k-6k rpm flat spot out. Problem is most aftermarket exhausts are tuned for top-end power - a pointless exercise on this bike, I think - if I'd wanted more top end I would have gotten an FZ1 or something else. I actually think the FZ8 powerband is just about perfect for the kind of riding I do, other than that flat spot from 5k to 6k.