Yes, a cheese board can be the main meal. A well-rounded cheese platter with a variety of cheeses, accompaniments, and other items like nuts or olives can make for a delicious and satisfying meal.  You may want to include some fruit, such as grapes or apples, as well as some cured meats and crackers to complete the meal.  Choosing a variety of flavors and textures will help ensure the cheese board is both flavorful and filling. Adding some honey or jams can also add sweetness to balance out the saltiness of the cheeses, making it even more enjoyable.