I love the grown up cuddle with Santa idea 
I go to 6 pm Mass on Christmas Eve once the DCs return from exH's where they spend the day. It's a children's Mass, goes on forever as it's always crowded, but when we get home we have a casual dinner with some kind of nice pie for dessert (choc pie for instance) or mousse, and then open presents from family and from each of us to each other that have been sitting under the tree, wrapped and ready. This clears the way for Santa. The DCs set out a stiff drink for Santa and a few mince pies, etc., for her to nibble on to keep her strength up. Reindeer food is sprinkled outside. On my old street all the neighbours used to light luminaria, but I am on more of a main road now. We light candles at the table for dinner and I have some plug in candles to set in the windows all night, an old Irish custom involves leaving a candle in the window on Christmas Eve to light the way for Mary and Joseph as they pass on their way to Bethlehem).
I try to get the DCs off to bed at a reasonable time because I am Santa here and I need to be up in the morning to get the cooking started so the Santa business needs to be accomplished before it gets ridiculously late. I remember how knackered I felt the next day after putting together a dolls' house until 2.30 am one Christmas Eve, making no progress until I found the right sort of screwdriver. Santa leaves presents unwrapped here. They sometimes take a bit of finding as hiding things really well but losing track of where they all are is her forte. I leave the tree lights on all night so it's all glowing in the wee small hours of the morning when the DCs wake each other to investigate their presents.
Christmas breakfast includes cinnamon rolls, scones, rashers, sausages, scrambled eggs, fresh orange juice, tea, coffee, hot chocolate.. Breakfast is usually eaten in pajamas. Lunch consists of leftover rashers and sausage, cinnamon rolls, salmon, brown bread, wine etc. They DCs also stuff themselves with Christmas chocolate. We eat dinner later, normally coming up to 6. I make a pumpkin pie (the DCs are American) and meringues (way ahead of time), and tiramisu instead of trifle because they like it a lot better. We have a Christmas pud too but only two of us like it (me and DD2). By dinner, most of us are dressed but pajamas are acceptable attire. More candles at the dinner table, and we take out the fancy crystal and use the Spode Christmas plates.
The week before Christmas we have a buche de Noel to celebrate my mum's birthday, usually in her absence. (Any excuse for my favourite cake).