I would lean toward the 7 racks of ribs and 2 pork butts. For portion control purposes, have your meat at the very end of the serving line and instead of hamburger buns, I suggest the Kings Hawaiian rolls. I like to pre slice them and bake them with a butter topping to shine them up, and just put the trays right back in the bags once they have cooled. Have a couple of sauces available, red and sweet is more popular, but have some spicy sauce just in case. Keep the pork moist with warm foil juices, or spray with warm apple juice. I also use a finishing rub on the pulled meat to make the flavor pop. I generally like to have a bag of the foam to-go boxes stashed (not in plain view until the party breaks up) and this way you get rid of most leftovers. Coleslaw is the traditional topping for PP sandwiches if you want to go that route.