I had actually written that in the first message. The arena is the most static part of the game. Once one builds it, it is done and because there is an attendance cap there is no incentive to change anything. In a game that is not very realistic anyway, there are several ways to allow a more dynamic arena. One way is to allow the user to demolish parts of the arena and change the category of seats. This is often done in real arenas but may be difficult to implement here. Another way which I would think is easier to code is to artificially age certain seats. Say 100 bleachers are removed and you can make up whatever reason you want. The player then has the choice to build 100 lower tier instead.