I think this is a standard functionality of every Cad/Cam tool in the world.
So Vectric made good enhancements the last years. But I think it is time to do a little more work on the basics.
In any software in the world, if i selct objects then the functionality is as follow:
If all selected objects have for example the same diameter, this diameter is shown and can be changed.
If the objects have different diameters the value is not shown, but I can put in a new value.
If not all objcts have a diameter property then this field is disabled.
All this is true for Layers, Colors, Linewith, and so on. In any graphic software in the world. Even Word, Excel and so on.
I know VCarve is not a CAD software but this is basic functionality