If you often add elements using drag&drop from the toolbox to the diagram canvas and you are not satisfied with the default size of elements, you can change it.
- Select an element which is of the size you want to set as the default size.
- In toolbox, right click on the tool of the element for which you want to change the default size. (The type of the selected element and the type of the element for which you want to change the default size need not to be the same.)
- Choose Default Size/Set by Selected from the context menu.
- Henceforth, all new elements of a chosen type (e.g. classes) added to a diagram using drag&drop will have the new default size.