Awesome essay, Mary J.!!! I'll link it over on HP Network.

I think there are readers who thought that there wasn't much going on in Snape's mind except thoughts of anger and revenge. They didn't count on sadness and remorse, or especially grief that would change his life. I think introverts understand Snape's life a little better, too, and extroverts seem drawn to characters such as Sirius, James, and Lily.