More food options, Fireworks for night games.
What's with stopping Drinks 20mins before full time? That's a terrible idea.
Really though, introduce a members draw. All ticketed members go into a draw to in $1k. Announced some stage in half time, need to have collected it by the end of half time. if it's not collected, the next home game it jackpots to $2k... etc... until the 12th home game of the season you have $12k up for grabs. Round 1 the following year, guess what, we're now at $13k... on and on it goes. Pop an add in the sports section of the leader, member number #### GA, missed out on $14k, make sure you get to the game next week for your chance to win $15k. Seriously as it grows, the crowds will grow also.
I assume you have a breaking point, say it's $50k? "We will be drawing members numbers all throughout half time until a winner is found".... or something like that. The joint would be packed out.