As for how companies work in the meantime, there are packages out there that can do the basics; in the CAD space, I've been able to achieve a fair bit with OpenSCAD, believe it or not. I chose this package because it feels more like programming shapes than drawing them with a mouse, but I wish that it had more features. As for requirements and bug patches, there are already companies out there using business models that are some variant of having "customers" pay specifically for features they want and also pay to expedite patches for bugs that affect them.
