I can only respond with God bless our substitutes!,,, I was one and the experience was the best money could not buy. I would do just what you have outlned in your plan, you may want to up the levels by pushing the class for before lunch and after lunch scoreboard work. If you are there more than one day, have them beat their record. I'd use class/yes in as many ways as you can use a class leader to gain the class following. Use those one second parties to add in fun.
Mr. Biffle I know cares about all teachers and I am sure will see you plea. In the mean time Deb Weigle has a cheat sheet for subs, if i can research the site I'll find it for you.
Annette