The shoulder-length hair in a ponytail seems like a very traditional wizard's hairstyle, so I think it's definitely fitting of Draco! :D For me, the longest hair I ever think of him with is around his chin and mid-neck, but I'm not a huge fan of long hair on guys so that's more to do with it.

Ooo, I'd love to see any pictures you find, if you go looking! *g*