I'm not even sure I know where to start! I have used Illustrator for a few years and I knew everything you taught here was POSSIBLE, but I didn't know how to do some things, and others I was really going the long way around. For example, I've made blends to create color palettes, but every time I went into the menus to do it.  Yeah I was today years old when I realized there was a tool just sitting there, ready for me to use! :'(  I've also been a heavy user of the pathfinder panel because I never could get the shape builder tool to work for me.  DUH - add the Alt key! 

There are so many more things but those are the biggest because they directly relate to what I do.  THANK YOU! Now to jump in to more of your classes. Yay!