When dealing with splines it will be helpful if you did not have to move the mouse away from the culprit every time you want to add a control point or remove one. The control and shift keys will allow you to select more entities but it would be great if these keys added or removed control points of the spline that is currently selected? True, could be difficult if you were actually trying select or deselect a spline. So maybe another key needs to be thrown in. How about the alt key? Or AC and DC to remain in the double key shortcut world of Revit?