Intuitive Constraints
When adding constraints in the Family Editor, the software knows when you are constraining an element to another element. Instead of simply warning you, it should give the option to create a reference plane and lock both elements to that plane. Additionally, If two objects are already constrained and another constraint within a certain tolerance is defined, the software should alert the user and confirm the new constraint or ask if the old one is to be removed. Also, any reference plane that has an element constrained to it should probably be a strong reference automatically. Revit assumes so many things that are not the usual intention or best practice, it's about time it started behaving intuitively.