I think the most important thing to consider when deciding what to wear for Christmas family pictures is the theme of your holiday. Are you going for a traditional, classic look, or something more whimsical and playful? It also depends on the location of your photo shoot - if it's outside in the snow, you might want to wear something a little warmer and more casual, while if you're taking photos in a studio, you can get away with something more formal. Ultimately, it's about finding a balance between comfort and style.