Images with things that are all the same size tend to not be as dynamic than those with shapes of varying sizes. Sometimes you want your work to have a static, even quality to it (just about every shot in Wes Anderson’s movies, for instance), in which case, size similarity is intentional. But, I occasionally see this technique being used by newer artists, who maybe don’t realize that making this one small change could make a world of difference in their work. Of course, we use size variation in compositions to create a sense of three-dimensional depth in an otherwise two-dimensional plane, but size isn’t just about seeming closer or further away, it’s about visual interest.
Along the same lines of size, is shape variation. The world around us isn’t all circles, or all squares, it’s made up of a wide range of varying compound shapes. That doesn’t mean that all your shapes all have to be off-the-wall crazy. There is beauty in shape simplicity. Otherworldly shapes tend to create a more successful piece of art when they are varied. Our eyes like to see different shapes together, and we can’t help but try to make images out of them.
For example, in my floating cactus island design, if I had made the islands and cacti all exactly the same size and shape, it wouldn’t work as well. The islands and cacti share similar shape languages, but are not the same. Try playing with even subtle variations and see how that can push the visual appeal of your drawings.
Both of these principles, along with silhouette, also play a huge role in character design. So, if you like to create characters, shape and size variation are always great principles to keep in mind.