Providing two meats, a couple of salads or roast veggies and two or three desserts is all that is needed to satisfy the hungry souls at your table. The more you have to choose from, the harder it is for the eaters to choose. How to fit it all on the plate ? There is only so much you can eat at one meal and many people travel from table to table ( family home to family home ) in one day.
Also, the more you provide, the more likely you are to be left with leftovers for a week. To avoid gastro, food should be refridgerated between courses and consumed within 2 - 3 days of cooking. You are less likely to forget what is left in the fridge if it is consumed within a small time frame.
I've cooked traditional and casual Christmas lunches in the past. Here's what I've provided for my guests
roast lamb served in gravy
roast potatoes, pumpkin and carrots
cauliflower and broccoli with white sauce and cheese on top
sticky date puddings in muffin size with caramel sauce, cream and icecream
CASUAL ( BBQ )
bbq steaks ( cut into smaller pieces )
mushrooms and onions
green tossed salad
plum pudding ( no name ) with home made custard, cream and icecream
mini pavlovas ( home made ) with cream and berries
Both have been hugely successful and everyone is full and satisfied. The casual meal had a lot more leftovers. We just ate salads and sausages for the next two days. The best thing about these meals is that I have most of the ingredients on hand already so there are no grocery blowouts. The only extra expense is the meat and a few veggies / salad things.