Most soup kettles hold 10 quarts at most, only about 40 to at most 50 servings, so I am wondering about your limit to "2 kettles". I would do at least 8 gallons. Also, are both the pork and beef for sandwiches? I am assuming they are, and the numbers would be different if the beef were plated.

pulled pork BBQ 1 pound per 4 for all
sauce- have a bottle for each table on the table
roast beef- 1 pound per 3 for all
gravy- at least 1 cup per 4
rolls/baguettes- 1 pound per 6
sliced onions- about 9 pounds
pickles-1 gallon

baked beans, 3 gallons per 100, have some meatless for the vegetarians in the crowd
potato salad, 50-60 pounds raw potatoes
coleslaw- 30 pounds cabbage plus add ins

vegetable trays- use veggie tray page, or do 2 classic relish trays on the same page
fruit trays- 1 1/2 deluxe tropical tray for 100 on the fruit tray page
chips, 1 pound per 12
dip, 1 pint per pound, minimum
pretzels, 8 pounds
Serve a punch or lemonade along with the appetizers, 10+ gallons

cake, least costly to provide a smaller formal wedding cake, plus a groom's cake, plus "kitchen cakes"- sheet cakes in the wedding cake flavor.