Unfortunately there is very little definition for "uniformity" in the art.The same Greek culture that gave us the first art forms, and in-spite of some philosophers like Aristotle writing extensively on the subject of arts in his famous assays (Rhetorics, Poetics and Theatrics), the main objective and the only "uniformity" in arts was to copy God-given physical nature and come as close as possible to forms of expression like acting, vocals etc.
I hope this helps
Ben