I am doing the Terran Marine build right now. I probably have the same files as you do. There is a way to make it smoother and rounder. In Pepakura Designer, with a file open, go to Settings, then Other Settings. Then Line Style, check the box for Hide Almost Flat Lines, then change Threshold from 175 to 165. I have built the right shoulder, right upper arm and I am working on the right shin, then the right thigh. I am just going to use Smooth On Smooth Cast 321 resin for covering the outside, then sanding it round and smooth, Bondo where needed and fiberglass resin and Smooth Cast 321 for slush casting the inside. The only files I would like to get now are the gauntlets, boots and the Gauss Rifle. The Terran Cannon that Raynor uses in SC2 cinematics would be great, just huge, like a proper sized Gauss Rifle. Good build you did there. Onward and upward for your skills now. Well done.