For what's it worth...
I did the whole package all at once, CNS carb, milled the head, added Pats typhoon intake and the same exhaust pipe with a port matched flange. It totally changed the nature of my bike, a big power increase across the full power range with no negative side effects. Plus it looks cool with the meaty pipe. And the pipe ain't too loud either so don't sweat it.
If your bike is garage queen you can skip it, but I consider this a mandatory upgrade for the guys that really ride their bikes, especially for you 200 pounders that need a little more torque to get the mass in motion. We've got a good group of motor bikes that ride together and the stock guys get smoked on our rides and one by one, they're all stepping up and making the mods.
Total cash outlay for the whole package is not a big deal either.