The other reason for the rise is to keep your shirt from showing when you wear a short jacket (like a PC). If you didn't have a full 2" rise, your shirt would show. And sometimes guys get PCs that are too short, and, even with a proper rise, they wind up with a pooch of white shirt between their kilts and jacket bottoms. Ditto for dancers - if a kilt doesn't have enough rise, the white blouse shows beneath the edge of the vest when she raises her arm to dance.

Most kiltmakers use a standard 2" rise unless the customer specifies differently.