To display a part family in a plan, you have to edit it in the 3D but not "in a new window": so you can resize it to display it as you want in the same way in the 2D.
But sometimes it doesn't work and the part family is displayed in any way! Any idea?
While resizing the family table (i.e. in the 3D), you have to save (directly with a CTRL+S) having taken care before activating (just by clicking) the first visible cell of the table you want to display!
This way, when you reinsert the table into the drawing, it is displayed correctly!