I made some basic oversights, when it came to the music at our wedding.
#1. The song for the presentation of the gifts was "The Servant Song". Turns out there are two songs with that name. The musicians played the wrong one. No big deal, though. Both songs are pretty good, and no one noticed.
#2. I spent at least a few hours, teaching Mary all the various songs at the wedding. I put a lot of focus on the opening song, Hear Us Now, Our God and Father, because it was the easiest for her to read/sing. Also, it was the first on the list. I didn't realize, duh, Mary is the Flower Girl. She didn't sing the song, because she was part of the procession.
#3. Similarly, with the ending song. We picked Battle Hymn of the Republic, because the wedding was on the Fourth of July, and it's a nice patriotic tune. (I purposely left that out of the music list I shared on this blog, since that probably would have revealed the wedding date). People didn't really focus on singing the song, since they were too busy watching us leave the church together.