When defining the seating chart for the location, the ability to assign an ACL to each Section, Row, and Seat (with inheritance, of course) would allow very granular definition of the venue, and give the ability to restrict portions of the venue to Preferred/VIP users, dignitaries, etc.
It should also have the ability to globally block and release sections, rows, and seats. This would be an advantage for staffing, since you could, for example, block selection in the balcony until the lower levels were full, or block limited visibility seats (nearly every place has them) unless absolutely needed.
Finally, it should have the ability to color-code and/or place an icon to indicate accessible and companion seating, as well as no-step seating for ADA compliance.