If you were to build a conversion that had a couch and a diner on opposite sides behind the cockpit, with a passenger side door aft of them, how does one determine which side the couch or diner should be on?

Is there a better side for the couch versus the diner...?

Off the top of my head it seems that the best view is more often out the right side so I'd opt for the diner to be on the right and the sofa on the left (facing the right window).
Roy

Is there a slide involved? That would determine it for you