Don't overdo it. A few years back, I went mad and had about 12 items on the plate - carrots, sprouts with bacon, braised red cabbage with apple,sultanas etc, hm cranberry compote, hm bread suce, pigs in blankets, 2 types of stuffing, mashed swede,roast potatoes,roast parsnips, turkey and gravy.
Insane. Loads left over, and leftover cooked veg are not appealing IMO.
Remember the more different items on the plate, the smaller amount people will eat. So for 7 people, I would do turkey, gravy, hm cran compote made early Dec, bought M and S bread sauce, carrots, sprouts, parsnips and potatoes ( small amounts of all ) plus gravy. I'd buy ready done pigs in blankets, stretching out rashers of bacon on Christmas Eve isn't much fun, and I'd make the stuffing ahead and freeze it - one sort only.
Concentrate on cooking the turkey. Once its done, cover in foil and 2 teatowels and then cook everything else. Have your potatoes parboiled whilst the turkey is in the oven so you can put them in a tray with oil once turkey is out. Hot oven for all the rest. Hob for sprouts and carrots.
Rellies always bring/make Xmas Pud. Get in accompaniments - custard/cream/ice cream.
We never have a starter - its too much. We don't eat til at least 3 though and tend to have posh nibbles and fizz on the go from around 12.