If you compare the head in the oval to the one in the square, you can see that I fixed a lot of the line width inconsistencies. The top of the head where the hair highlight is and the collar needed the biggest fixes. Its important to establish the line width early and make it same all around. It lends to the believability of the world you are trying to create, and helps with the overall harmony of the picture.
Since Chewy was the only one to take a guess, I added the shoulders in her honor.