As someone who uses Solidworks regularly for mechanical designs this problem basically makes FreeCAD unusable in any real sense. There isn't a single model I've

As someone who uses Solidworks regularly for mechanical designs this problem basically makes FreeCAD unusable in any real sense. There isn't a single model I've made that I didn't need to do something like in your example. When designing, a lot of time is spent trying to model it in such a way that one dimension change will propagate down the line so you don't have to worry about adjustments causing something like two holes to misalign. It's super easy to miss small little things that would make the whole thing not work, so you design to avoid it. Essentially, the professional programs are setup so that you make basic shapes and relations and then put in your final dimensions at the end once the conceptual design is complete.