For the advance wig panel, you should ask Celtic_Sakura, she is in the Arda Iron Wig challenge and she is awesome!
For myself, I would like to see a panel about draping techniques and how to use it. I usually try to modify a pattern but I would love to learn how to use these techniques instead. Engineering with big props, how to make them and make sure they won't crumble. Costume on a budget, how to use everyday stuff to make extra-ordinary accessories etc.
Follow your dreams, who knows where they'll get you?