Basically what I've done with each tune is do one verse with no variation, then have one or two more verses, with variations. I tried to not get to elaborate as to stray away from the song or make things super difficult. But I'll tell ya one thing, it sure beats just playing out of him books and repeating the same thing for several verses!
So I've put my book on sale, under the page "Christmas Arrangements", with the hope to share these arrangements with horn players all over. It's a very convenient collection of about 16 Christmas tunes, all specifically for the range of horn, with added flavor to make the tunes fun to play and to listen to, while still sticking to the framework of the original song. And again, it sure beats playing out of a hymn book!