A good layback has the right leg in an 'attitude' position which is up and away from the body. All too many skaters have terrible leg positions. Both the clips above show excellent leg positions. There is a lot of room for interpretation in the way the skater holds the upper body. The Dorothy Hamill clip shows the classic position, which is still one of the best.
Most skaters focus completely on the upper body and forget about holding a good leg position.
If you want to stand out, make your layback a complete package. This clip shows that a spin doesn't have to be fast to be great. It will take you awhile to download, but it's worth it. This is an extrordinary spin. You have to have your bones surgically removed to be able to get into this position.