Try to incorporate something sweet, tart, bland, salty, and sour in each meal. Strive for contrasting and attractive color combinations. Aim for a combination of crisp, soft, chewy, and firm. Mix and match shapes and sizes, incorporating items that are flat, round, long, chopped, shredded, heaped, tubular, square, etc. Try to provide both hot and cold foods, perhaps following a hot appetizer with a cold salad.
People love to eat foods that are attractively presented.
I've also done couscous in timbales and changed the color of the plates for every course to make things visually exciting. Everybody loved it and it didn't cost any more. Style of service. Varying the style of service keeps things interesting. When you're ready to map out the menu for each function, keep in mind that if your attendees will be staying at the hotel for several days and eating mostly catered meals, you need to be careful not to repeat food items from meal to meal or from day to day.