The thing that limits us from being able to do some pretty awesome stuff within our CAD/CAM software is either us having the time or the capability to create automation programs to help make your life as a programmer easier. I have created in Inventor, ilogic rules that creates soft jaws and a stock solid for me to mill from.
I have also created today the same ability as an addin for Fusion 360. to where you can select either from a standard jaw size or create your custom jaw size. Then define a box solid to be created to define a stock solid.
Here is the link to this video.