There is a street that does this in Alameda (3200 block of Thompson), and I'm told they have a covenant/contract requiring you to overdecorate when you buy a house on that block.
One side effect of my overdecorating is that it’s inspired my neighbors to put up some lights. More lighted houses every year!
Of particular note is the Christmas tree, which as far as we can tell originated in the (decidedly non-pagan) 16th century: "The earliest mention of customs like Christmas trees are actually ascribed to Martin Luther. The story goes that during a winter evening stroll Luther was overcome by the brilliance of the stars in the night sky, painting the background over the evergreen forests. In order to capture that moment Luther cut down and erected a tree in the main hall of their house, covering its branches with lighted candles" (Bruce David Forbes, Christmas, a Candid History, 50).
Overall, specific rituals aside, having a big family celebration around the winter solstice really seems to do wonders for the mental health of people at high latitudes- and has been done consistently since long before Christianity. As a parent in a non Christian family, I find it to be incredibly valuable and important and I take it pretty seriously, but without any sense of it being religious.
Every year, some people need to marginalize Christianity's contribution to Christmas despite ample evidence to the contrary. I attribute it to an ignorance of how religion digests culture and evolves, plus the usual resentment towards that religion in particular.
Or as long as you over decorate once a year is good enough?