I think that the suggestions so far have been good ones and food quality is an absolute must along with a generous quantity. One thing that I think is often forgotten though is morale. The cooking of 300 or more meals, three times per day can be tireing to say the least. Be sure to let the cooks and other kitchen staff come out and have some fun with the campers at meal time. Kitchen staff skits, songs, and the like help build a relationship between the staff and the campers.
Here is a couple examples,
Idea #1 Monday a couple of the kitchen staff come out in hillbilly attire (bibs a