As for my must-haves, for me it's stuffing and gravy. Turkey is a merely a vessel for stuffing. But this year I'm thinking of making dressing, but it's never as good. However, I already have extra poultry fat and stock handy, in case I go the dressing route. I don't think I want to know how much fat I'll have to add to make it taste anywhere near as good as stuffing.
My other favorite is sweet potatoes, the Red Garnet ones, which my dad called yams. Mine are parboiled, then braised and basted in a mixture of butter, maple syrup, brown sugar, cinnamon & nutmeg. I add Scotch whisky when it comes off the heat. The yams absorb the sauce and become heavy, so if there's any left after dinner, you can add a dollop of whipped cream, and they taste much like a pie without the crust.
Sunset9, besides my dad, you are the only other person I’ve come across who browns their flour before making the gravy. He did it every time he made gravy, and so do I. I browned mine Sunday in a seasoned cast-iron pan (stirring frequently with a silicone spatula), sifted it, and it waits in a zipper bag. I've scorched the flour in the past, at least it's a cheap thing to throw away. I like to add port-soaked-prunes to my cornbread stuffing, reserve the port, and it gets whisked into the gravy along with stock. So good.
Compass Rose, I think coconut cream pie sounds wonderful, and if someone wanted to bring or serve that or any other kind of dessert, it would be fine with me. But there are always those people who just expect traditional pumpkin pie, even if they're still too full to enjoy it.
Yes on Brussels sprouts, as long as you can serve them before they become bitter and stinky. Personally, it's an overwhelming NO on green bean casserole, unless some of your guests will eat it. If a guest doesn't cook but considers traditional GB casserole their specialty and wants to bring it, you must graciously accept it. But sometimes you can talk them into bringing something else without their knowing it. I hate to be ungracious, but if someone brings it here, they're the only person who eats much of it, and I either have to dispose of it when they're not looking, or send the mostly uneaten casserole back home with them. I hate to waste food like that, so if I can divert or distract them enough that they’ll bring something that will be eaten and enjoyed, all the better.