I actually have worked on more serious posts, but they aren't polished enough for me and may never be. So instead, you get this.
More index card doodling: typical default filling of seats for various event types, overhead representational view.
(And I illustrate this as the sister of a Highland piper, someone who like bagpipes and who has been to performances populated by people who are as enamored as I. Because...no matter how much you love the pipes, them are LOUD. Especially in a small enclosed space.)