The first few 3-D models I've made are entirely flat or boxy, with few or no curved surfaces. The boxy look doesn't seem right. That's when I thought of using sub-surfaces and smoothing, to create a ball within a box for every box made. However, given the problem that paper has or curving only one way, and also getting the right unfold (always a problem in Blender, not sure of a 3ds Max-Pepakura duo) and cuts, I would like a hint, particularly from those whose models have curved the most. Then again, maybe size does matter, as I'm still making models as large as six inches at most.