The real way to fix the throttle response is with the reflash. Most if not all of the effect people are feeling from this R6 tube is an illusion because the real throttle response is handled by the electrically-controlled butterflies, off the throttle position sensor. What this means really is that no matter how fast you yank open the throttle, the secondaries are controlling the response, period.
The Guhls reflash totally changes how quickly the secondaries open up; they are much more aggressive on opening, along with all speed and ignition timing restrictions being removed. And believe me you do NOT want a 1/6-turn throttle on this bike if you reflash it, it is a rocketship.
Yes I know it's $300 but forget every other mod, if you want the bike to run like it should, smooth, powerful, responsive, do the reflash and save all that money that you'd spend on pipes, headers, etc.
Just sayin'.