3 dips- 2 would be plenty- 3 quarts total, 1 pound bread, crackers, or chips per 15
tomato & mozzarella 3 quarts grape or cherry tomatoes, 2 pounds tiny mozzarella balls
veggie tray w/dip- with this menu, I would do a fruit tray, you already have plenty of vegetables.See either the fruit tray page or the veggie tray page

cold cut/cheese tray for sandwiches
chicken salad,
because you have both, use the reception level guide on plan for 100, use 1/2 each for 50

80-100 slider size rolls mayo and mustard

quiche made in small muffin pan,
if mini, 2 per person, if small, 1 per person

pasta salad, 3 pounds dry pasta plus add ins
green salad, I would instead do sandwich fixings with lettuce, tomatoes, pickles, olives, etc- see the sandwich planning page, or5 one of the salad that hold in that section on the site.