What would really make my day is a format painter. I'm so used to it from the Office suite and other programs, it could really be a time saver here.
I would also like to see this added.
Some functionality for this sort of thing exists.
If you add a style (with the style customizer) to a component you can copy the style and paste the style into other components through the style customizer.
I'd also like to see this added. It would work similar to the copy/paste function behind the scenes and completely overwrite the style customizer of another component if you used it. Although it would only be available for components that are the exact kind of component you're formatting from.