Not sure which model of 636 (A, B or C) you have - but it's an absolutely storming engine as standard.
I sold mine (C6F) and bought a 955 Speed Triple so that I'd ride more slowly - if yours is running right and there's nothing wrong with the engine then IMO there really is no need for any more power on the road; if you can use all the power the bike has you're probably riding too fast
But if you want a bit more drive out of the corners - then as plenty have said dropping the gearing is the way to go. As standard the C model 636s are geared to indicate 186+ so you can afford to drop the gearing 10% and still have an almost unusable top speed.