We used to generally have smallish but very traditional Christmases when I was younger. sometimes just the 4-5 of us (DBro is 10 years younger than me, so big gap). They would follow a schedule that never changed and had been developed over the years to suit us perfectly. XMas eve the prepping of the dinner for the next day, mandatory Reading Of Dicken's Christmas Carol By Father, followed by TV. Midnight Mass for mother after we'd gone to bed, then when she came in they would do the stockings and the presents put under the tree as a surprise for the morning.
Mornings would be stockings, then visiting some of Dad's relatives while Mother cooked dinner, late (post Queen's Speech) dinner THEN pressies. Some years my DGM & the single uncle who lived with her would come, one year we had an American uncle & his son staying, a few times friends of mine with family issues would stay. House was always well decorated with a large tree in the hallway, real holly etc. We would have run-up events every year but these tended to be watching Holiday Inn and going into London to see the lights & shop/have lunch at F&M, and maybe a church pre-Christmas Fete. When Mother died, we carried on all the same traditions partly in her memory, partly because we really enjoyed doing Christmas that way. Only real difference was that I would do the stockings & putting the presents under the tree, and the cooking. We even had a traditional list of the kind of things to go into the stockings!
Roll on a few years, and I live with the cats. DBro goers to his MiL in the West Country for their family Christmas, & DSis either goes to Scotland to see 2 of her sons, goes to another (married with kids) son, or stays in with the 4th son, so there's just me on my own with the cats. TV, Mumsnet, gaming on the PC, eating party food when the mood strikes me. Then Boxing Day DSis comes round with nephew no. 4 and we watch films & eat more party food. Cats get treat food like Tuna Loin & cat soup instead of their regular food, not that they know why the day is different.
Minimal decorations here mainly due to Cats - maybe a couple of battery operated table trees, some window clings and lights, and a wreath on the door. There's a ginormous cat tree where I used to put the Christmas tree before Cats, and I know they would wreck any big tree I put up!
One of the big plus points is no expectations or demands from anyone else, I can do what IO want when I want. If I want to eat at 10am or 6pm there's nobody else to fit around, if I want chocolate for breakfast there's no comments or tut-tutting, no arguments about what to watch on TV or demands to be social when I want to kill monsters.
Another big plus is the cost, or lack of cost. Decorations I mostly have everything I need, though I may get a couple of things I fancy for about £10. Quite a few years ago when I had shed loads of money coming in & DSis had 3 boys still living with her, I catered the meal from M&S to cook over there and I think it cost around £100 for just that main meal, and that must have been 12-13 years ago. Now I spend a total of around £50 extra on indulgent party food from various supermarkets for the entire period.