I’ve made quite a few 3D printed parts with holes. For your leg geometry I’d say meshes are the way to go - your option b. There are several reasons for this:
- As you have found out, the SDiff function requires a lot of CPU time. For as many holes as you have, this will make development a very slow process.
- Even if you got the SDiff approach working you’d still have sharp edges around each hole. That will lead you to the filleting problem, about which there are lengthy threads here already - see this one in particular: Variable fillet in GH?.
- There are several ways to smooth mesh edges; I’ve seen some really nice looking results that started with simple polygonal patterns on curvy surfaces. I don’t use meshes myself and I don’t know much about them, but there are people here who do.
- 3D printing is really mesh printing, so you may end up with better results if your entire development is done with meshes.
PS: I tried your GH file but I could not get it to display anything. It loaded OK and looks fine in GH, but I couldn’t get anything to show on my Rhino screen.