Mixed Hor D'Oeuvres and veggies to start
5 Large trays Ceaser salad
5 Large trays Mixed green salad
6 Large trays Herbed pasta
350 pieces fried chicken

We're thinking of adding pulled pork and sausage and peppers to the meal. I've seen your other threads where you suggest 1lb per meat per 5 guests. Would this calculation still hold true? so 60lbs pulled pork and 60lbs sausage and peppers?

Also, I noticed in a thread for freezer meals you left out garlic. Does garlic not freeze well? Should I leave it out of my S&P if I plan on freezing them?

Usually the large tray is calculated to serve no more than 30 (most commonly 24) so I am concerned about only 6 trays pasta.

You will also want bread, at least 12 pounds per 100, and a hot veg (broccoli, roasted mixed, etc), about 65 pounds, would be a good addition. Roasted veg can be made ahead and served room temp. If the pasta is hot, with roasted veg it makes an adequate vegetarian entree. For this crowd of 300, you need to have one dish that can act as a vegetarian entree.

Now the meat.
The 350 pieces chicken makes a fine second meat. With your essentially Italian leaning menu, may I suggest meatballs instead of pulled pork? If you did meatballs and sausages plus the chicken, you would do 1 pound meatballs per 5-6 (3 quarts sauce per 10-12 pounds) plus 1 pound sausage per 5-6, but then add in an equal weight of onions and peppers to the sausage.

2 pounds grated shaker Parm per 100. If you get the fancy stuff, add a little more.