Since the anniversary update it is possible to completely switch of any touch input as long as the pen is active. Fixed any of the palm drawing issues for me completely! I only use the surface pro 2 with the wacom digitizer though so it was never a huge problem to begin with and I am not sure if it works just as well with the new pen tech.
I just played around with Leonardo and it looks really awesome. It marries the infinite Canvas of Mischief with useful sketchbook-like ruler and perspektive tools. The ellipse tool is even better than in sketchbook imo. That’s basically all I always wanted. Why is this software not better known??