AS for feedback, I will take on up to 6 people at once in Quake 3
Although other than that, I would simply suggest a few new/different games, some of which are
Call of Duty: World At War (Or any CoD for that matter),
Smash Bros any of them (I don't remember if you guys did that one, but it's a great multiplayer game), and Nazi Zombies, which is a sub-game of Call of Duty World at War, but you could have a competition to get to the highest wave count, and I PERSONALLY know 12 people who show up just to play that game.
In addition, you should look into getting Heritage to sponsor the event and have an espresso machine on site, because I know a lot of people would buy coffee, while it is true most people drink ener-crack drinks. Also, with the addition of a coffee sponsor, I know you would attract a lot of the 20-30 year old state and private contractors that game.
Also, you know what, name tags might not be a bad idea. I have found at any even, that helps people be more social in general. You could whip up something cool for the design of those. Wouldn't cost ya too much to get those done at Capitol Copy.
And, I know a liquor license is a huge and complex thing to get, but if you can get one of the local catering agencies or bars to sponsor you, and they come bring their own off-site liquor license, along with a personal stock, and sell their own booze, that would save you a lot of hassle, and you would be able to have a 21+lounge, thus giving your event some of the tried and true allure of Dave & Busters.
Also, having some sort of physical activity at some point, so our muscles don't turn into jelly would be advisable. Something organized, like a Counter Strike style Paintball course, where you can add more money to the entrance fee for the optional unlimited paintball play (thus aiding you in covering costs) or, once again, you could look for sponsorship. Someone that would be likely to sponsor you for this is Play It Again Sports, as they are not centrally located and don't get much exposure.
And above all guys, work smarter, not harder.
Sponsorship can take a lot of work out of things.