I agree, I'd definitely go for the sprocket change for more torque. The bigger rear sprocket and a smaller race front sprocket will give less top end but you'll get there much quicker.
It's worth bearing in mind if you do go for race gearing your speedo will be out by 7-10%, so a speedo healer might be of use.
I changed the gearing on my old R6 and it was amazing, wheelied a lot easier and I didn't miss the top end at all. I think I'll be getting a Renthal chain and sprocket kid soon for my 636..