Here are the two best Christmas experiences we've had in Italy.
One year we stayed in Naples before Christmas and visited the little streets that sell the "ingredients" for making the nativity scenes (presepi): people, animals, vehicles, food, houses, flowers, trees, the tools and costumes for various occupations and activities, even things like tiny bricks and stepping stones, etc. All different styles and sizes in many shops and displayed on tables. The people figures are not just the usual shepherds, wise men, angels, and so on, but U.S. presidents, soccer players, children, grandmothers, pizza makers, police officers, you name it. Some were mechanized and could chop down a tree or sew a shirt. Naples in December was calm and inviting and fun (we kept wondering where all the "grit" and craziness was --- so much else to do there, too.
The other place would be a lot more trouble for you to get to. It's a very small town about halfway between Florence and Ravenna called Portico di Romagna. Every year, the townspeople, schoolchildren, and various artists and groups of people all create presepi to fill every nook and cranny of the town. These literally line every street and project from the walls of people's houses. Some of the nativity scenes are traditional, but many are made from unusual materials (shells, the guts of old radios and TVs, musical instruments, nuts and dried flowers, recycling stuff, broken flower pots, pebbles, driftwood), and quite a few are political or satirical or funny or larger than lifesize or just plain weird. Maybe my favorite one was made from old electronics and wood scraps and featured a crowd of wooden people surrounding the manger photographing it with real cellphones. It seemed like the people in the town make different ones every year. We stayed several nights in an old convent in town and saw that while the town was quiet on weekdays, there were throngs of mostly Italian tourists there on weekends.