I model exclusively with OpenSCAD and a shit ton of math. (Full disclosure, for some of the most absolutely complex things I’ve done, I’ve written Go code to generate OpenSCAD code. But it’s not often that I need that.) And I make some pretty complex things. I’m currently working off-and-on on a 3d-printable mechanical keyboard, for instance.

OpenSCAD, in case you don’t know, is a straight up programming language for doing CAD. It doesn’t even provide you the option to adjust anything with the mouse.

It’s hardcore, but it does the job.