As I write, I am awaiting my new 2011 Road King which I'm having a Stage 1 (pipes, air cleaner, tuner (Screamin Eagle tuner)) and a Stage 2 (SE 254 cam & pushrods) installed. I think that alone, without going to work on the heads, will far and enough supply the extra hp and torque I'm looking for. I ride 2 up mostly.
BTW, I decided to go with the Screamin Eagle tuner which programs the onboard ECM instead of having to install a piggy back module (e.g., PowerCommander) which may cause problems with the ECM. I can always go back to the SE tuner when any future modifications (although don't plan on any at this time) are made.