Im redoing my Shakespearean portraits as well.
I did this Titania portrait in school in oil. The Crock illustration turned out pretty well, so I decided to redo some of my others.

This one was always my favorite. I love the girl who modeled for it. I thought she had a great spirit look about her.
I wanted to do a more detailed realistic look in illustrator, so I thought this would be a good start. It took a lot longer then The Crock, about 45 hours. The face has a lot of layers and transparencies. Im pleased with it.

Progress images seen here.