164 for you--maybe even slightly bigger depending on how much maneuverability (164) versus carving performance (longer) you desire. Sean likes to put people on bigger Razors. Honestly, I never understood that. But then again, I was basically looking for an amped-up freeride board that could carve exceptionally well and rarely needed to off trail. Given that the Razor already has much more edge and a shallower sidecut than your average freeride stick of the same size, I saw no reason to go much longer than I would normally ride.
I'm about 145lbs and short at 5'4." My 164 Razor is at the upper limit of stiffness for it to be enjoyable for me in all conditions. (Keep in mind that Sean will tweak stiffness to your weight and riding style.) I also ask for the same dampening as his Saber BX series boards--which is really nice for icy/hard conditions. Lastly, I like a radial sidecut on my softboot carving boards--between 9 and 9.5m. But that's just my personal preference.