Communion time is a time for receiving the blood and body of Christ. It is a meditative time and the music chosen for it should either reflect the Eucharist, or, be a song of meditation. I have written quite a few songs that are great for meditation and prayer. Some of the songs I have written for communion include some old hymns that are well known by the people who attend mass and they can sing along without the words because they are so familiar.
A great Advent song is Come, O Come, Emmanuel. It is 3 parts and easy to learn. Here is the YouTube video for it. Click here to see the video and hear Come, O Come, Emmanuel
Take for example, God In Three Persons, Blessed Trinity. This was based on the old Hymn, “Holy, Holy, Holy”. Once people hear this melody, they sing along. There is no need to make an announcement before Communion.
Then there is Psalm 147: Praise the Lord Who Heals the Brokenhearted – Amazing Grace. On the verses, the solist sings a counter melody to the melody of Amazing Grace going back to the refrain after the 2nd verse. For the 5th verse, it is sung in unison bringing in the congregation. Depending how long communion is, a 2nd verse from the original Amazing Grace can be added before going back to the refrain and out.
In any case, I know your congregation and choir will love these hymns.