I looked at this collection of pavilion images from 1380-1415, and saw an interesting pattern. The valance or shoulder of the tent was hardly ever undecorated, if only by two or three horizontal bands of color. The walls were most likely to be devoid of decoration, and the roofs fell between the two extremes.
I have a pavilion I plan to decorate, and finite time before I first intend to use it. The information above will inform my decoration campaign, and may be useful to others.