Whatever your faith I believe that there should be room to express creativity within that faith. I'm thankful that I have that! I am thankful for parents that allowed this even as a young child.
The nativity for me signals the start of the Christmas season. As a child I would spend hours playing with the set. It was old, but sturdy, and Dad had built a rough barn for it. Every year it was one of the first decorations to come out. While I don't remember a lot of detail about my play, I remember that it captivated me. Once when I had all of the characters out of the stable, Mom asked me what I was doing and I told her they were "having a hoedown!"
This may seem irreverent to some, but it made the story of Jesus real to me as a very young child (I continued to play with the nativity into early adolescence and took great pride as a teen when I was allowed to help Mom set up the porcelain, "no touch" set.). It allowed me to worship my savior, to spend time thinking about who he was and is, to put Christ in the center of my Christmas! Sometimes I think that I need to stop the busy-ness and just sit down on the floor and spent time with Jesus!
A few years ago Mom gave my children a nativity they can play with. Currently Elli's shepherd is asking other Christmas ornaments if they've seen his shepherd stick. Yes, the set will never be pristine... shepherd sticks will go missing, hands, noses, ears will get broken (superglue is our friend!), but the creativity in honoring a little baby born so long ago is worth it!