How much beer/liquor for a wedding reception?

We're having no more than 256 guests. We're having a fruity drink called a$$ crackers that uses vodka, and 3 of the big jugs of vodka will make 18 gallons of the drink. We're also having whiskey and coke, and planning on getting a case (6 big jugs) of whiskey and about 12-20 2 liters of coke. This will make roughly 16 gallons of whiskey and coke. We are currently planning on roughly 2 kegs of beer (not sure if we're doing kegs, or buying an equal amount of cans- the nearest place that sells kegs of the beer we want is over an hour away, though we might have another option to get the kegs). Does this sound about right for this amount of people?