Pagan Christmas

I'm reading a book of that title that talks all about the Pagan origins and ethnobiology of many Christmas customs. I knew some of the stuff, from reading about Germanic cultures and happening to stumble upon stuff that looked like it was brought into the Christmas tradition.
Surprisingly by learning about the Pagan influences I'm learning a lot more about the Christian religion and gaining a lot more respect for what the Christian religion is.
Basically the Church was against a lot of the "heathen" cultures but they couldn't get the people to stop so eventually they realized that they had to go with it and try to just change the meaning slightly to have it relate to Christ.
Despite the violent oppression of the Church or churches, or just some people writing nasty things about local cultures, the end result can be seen as a pretty awesome religion. I mean who defines a religion, the church or the people who practice it? Now of course there is a lot of people killing other people because of religion, or just using religion as an excuse. But basically the good side of the Christmas spirit is traditions that include a wide variety of traditions and cultures from around the world with the general feeling  of "Peace on Earth" and in general Jesus represents a Westernized Buddha type thinking where we will have a "Kingdom of God" on Earth, or a hope for the sun, wealth, and goodness in general.
That's a pretty good mindset, and a pretty good religion. Now is there some nasty parts of history around all these traditions? Of course. Is it good to learn about these? I say definitely. But when we celebrate  just know focus on the fact that our traditions come from all over the world and so maybe we should be open to newer and more diverse traditions coming in.
Most of the traditions have Shamanic roots, from the World Tree, to the color schemes of red and white, to flying reindeer. If all of these things can now be considered Christian. Then anything can be.
Santa has roots in St. Nicholas in the 4th century middle east, but most representations of him in Germany looked more like Odin/Wotan and apparently the Christmas holiday spread to Tibet, where they depict him as A Buddhist Shaman (still with the same outfit and beard and face.
Jesus took on meanings and roles of older Sun deities. And why not?
A lot of stuff will go around facebook showing these pagan origins in a negative light.
Why not just enjoy the celebration and learn about the pagan origins, and we have developed enough as a society where we can filter good from bad. Worshiping trees I think is good. Human sacrifice on those trees.. obviously bad. Decorating them with lights... I would say good right?