Honestly you do not need to worry. If people are going to be demanding and ungrateful that’s their problem not yours.
But, if you want to make it easy, you could have canapés leading up to dinner, rather than an actual first course.
Buy a couple of boxes of voul a vent cases, fill with mackerel or salmon or crab mousse, top with a tiny slice of cucumber and a sprig of dill.
Buy a pack of German five grain bread slices, butter them and cut into small squares, top with gravadlax (salmon or trout) and a tiny slice of lemon.
Have cheese sticks or pretzels or something salty/crunchy on the side. Plus a bottle or two of prosecco to hand.
A goose is an extremely forgiving bird, it’s so fatty that you can’t really go wrong with it, it will be moist and delicious. Buy it frozen if you want to keep costs down.
Some red cabbage (ready made, from M&S), plus a tray of sprouts or a tray of carrots and parsnips to roast, some potatoes parboiled the night before (or even earlier in the month - you can freeze them and they come up beautifully).
M&S do a lovely orange trifle that is very light, so perfect after a heavy meal, or you could make coffee with baileys.
Most importantly, do what is best for you! Christmas is not about perfection. It’s not about struggling under the weight of expectation.