Having been the go-to guy for "catering" the past several "family" gatherings (minimum crowd 30, max 95!) your menu looks good with just a couple of comments:
- Stuffed mushrooms...I love 'em, lots of options, great variety of taste, etc....but they will occupy a lot of oven space/time (for an appetizer) if planned for a large crowd
- Ice cream: perfect dessert, almost universally liked...but hard to readily keep and serve for crowds more than 10 or so unless you have access to some near-commercial cooler space or a dedicated large residential freezer.
I'd portion the cooking for 40. Most of your meal list and some of your appy's will keep or otherwise make good leftovers if (on the slight chance!) some is left over.
I have a small BBQ smoker, a large BBQ smoker, and a gas grill at home. If it can't be cooked on the smoker, it's not part of the meal.