Comment by jacquesm

I use OpenSCAD for parametric stuff and it has served me very well, even if it has a learning curve and some serious limitations. The trick is to stop thinking interactively and to treat the shapes you want to make in a more generative manner. For instance, you could try to fillet or chamfer an edge, or you could create that edge using a sphere or a shape tracing a path and then tying it all together with a hull. But it can take a while before you become adept at seeing how shapes decompose into simpler shapes.