What I’d recommend is getting a scrap of paper, dividing into small squares, and quickly sketch out 4-8 possible ideas, keep it small and rough and you can quickly compare how the ideas will look and pick your favourite.
Could have snow and a moon, a big window if you want it still in a house, a snowman, a sky and santa in the sky, lots of christmassy ideas.
I’ve donated to Krita and I’m rejoicing!