The size of the print piece should be in relative relation to that of a game case. It seems only logical for, well, firstly print cost issues and then distribution (if possible) during the show. However, that aside, in terms of the project the dimensions must serve the best relationship with the content. With that in mind a game case still seems most appropriate as it is the source of the project, and what the project is all about; the video game.
Incorporating a more balance ratio however, I chose to alter the dimensions of the standard dvd case (7.5 x 5.375 inches), for the larger of course, to represent the golden ratio.