The 1.8 20v isn't exactly the most refined engine in the world and beyond a remap the diminishing returns hit hard. And turbo lag is no fun!
Jason, if I were to do it all again it'd still look exactly the same! Only thing I'd change would be some smaller lighter wheels for track/fun - and maybe strip the interior properly and chuck in a pair of Recaro Pole Positions. Those 19's looked good but in all honesty they were a little too heavy and you could feel the extra weight when turning into the corners. The S3 was always a little fat boy and dropping a few hundred kg's would make a huge difference; probably more than chasing power figures.