One thing that I have always been guilty about is the recommended number of seats in a room. Which is the best way to determine a 'good' number? I have always put seats away from walls and surround speakers. My headache has always been how to determine when the seats become too many.
Well, I wouldn't say that there is a standard way of doing this because the recommended number of seats would vary, depending on the size of the room. I would place more emphasis on how far the seats are/were, from the speakers.