There are so many variables. It's hard to tell what's going on.
For example: I have a setup similar to what HD Street Performance recommended in my 117. CR480, Vance & Hines Power Duals, and S&S Grand Nationals with decibel reducers in to keep low end torque. The bike made 112/128 in a 5th gear pull.
Now my friend's bike with a 114, three cubes smaller with the S&S 475 cam, decatted stock header, and same slip-ons as me, Grand Nationals with decibel reducers. BOTH bikes tuned by the SAME person....his 5th gear pull was 116/129. Maybe the conditions were right for a few more ponies? Who knows. I know that if my bike had 3 more HP on paper, I probably wouldn't notice.
I'll also say this: I'm no expert but your torque curve with that exhaust combination seems to be defying all rules when it comes to performance. Theoretically there should be a massive low/mid range dip. Yours hits hard and keeps going. If it feels good, ride on!