How about a baked potato bar? Have lots of baked potatoes, already hot and split open. Offer roasted broccoli, shredded cheeses, brown gravy or sausage gravy, cooked bacon, pico de gallo, sour cream, chopped cooked chicken, butter, etc.
Or make a lot of small-size meatballs (or buy a Costco sized bag of prepared meatballs that you just have to heat up). Then offer different ways to eat the meatballs - on a hearty roll with marinara sauce and shredded cheese, or in BBQ sauce over noodles, or with roasted vegetables.
Or hearty salads? Set out the basics (lettuce, tomatoes, cucumbers, etc) and a lot of choices for toppings, like hard boiled sliced eggs, chicken (just cut up a rotisserie chicken from the supermarket), sliced ham, cheeses, diced onions, edamame, etc. And to accompany the salads, nice baguettes or good rolls.
You could make a good soup - homemade chicken noodle or a beef vegetable soup and serve it with nice breads.
Or a spiral sliced ham from a store, with a big pan of homemade macaroni and cheese and some nice rolls?