We could always have a top tier say behind each goal that is non season ticket but only opened after the lower tiers have sold out, therefore not the smattering of empty seats you see at the Etihad, all the seats will be sold out close to the pitch and then the upper tier sold on a game by game basis. Wouldn;t be noticed by the cameras and we would retain the intimidating atmosphere. 50,000 then an extra 10,000 as and when it is needed. Even allow 5000 away fans - better atmosphere and more money! Also one of these tiers could allow almost 'giveaway' prices to students, schools unemployed etc one to boost attendances and two to increase the overall fan base.