Where to Sit?

Suppose you choose to sit in a seat (pink point) anywhere on the circle below, but not behind the stage. Which pink point provides the best viewing angle of the stage? Mentally answer this question first. Then slide the slider completely. What do you notice? Feel free to change the size of the stage at any time by dragging its white endpoints along the circle. Feel free to change the locations of the pink points at any time as well!