This is what going on today, people dealing with other tradition thats not of God (Jesus) and not of the gospel that was preach.
The tradition that's not of God is believing the pagan teaching that created things are anything more than just created things. Why do you seem to believe the pagan teaching? I mean, you seem to believe that decorating a tree = worshiping a false god, just because some pagan people said it is. What I don't get is why we should believe that pagan teaching. The Bible, instead, teaches that believing that tree has any kind of power = vanity. Do you think when people put up a Christmas tree they are following the pagan tradition of believing that tree has some kind of supernatural power, or are they instead separating themselves from that pagan tradition, and recognizing the Biblical truth that "they cannot do evil, neither also is it in them to do good"? You say they are "dealing with other tradition(s)," I say they are setting aside those traditions and simply believing the Bible.
The gospel that was preached is still the same gospel that Christians preach on Christmas, Easter and what you call "Sunday worship." I'm glad you agree with Act 10:15, and I sincerely hope that one day you'll be able to see that whatever God chooses to use to teach His word by which He seeks to cleanse people, we have no right to call that work "evil".