Aye, Calgacus,

If we are talking about conveniently putting it on, shorter works fine, but it is the sleeping part that adds length.

Crows4Hire, I do not mean to insult you, but please note all of the terminology:
The Great Kilt is the wrapped length
The Philabeg is the "little kilt"
A Plaid ("PLAYED") is a separate blanket/shawl/scarf and, depending on the wearer's inclination, can go anywhere from a big bandanna to several feet, wrapped or draped accordingly