The main purpose of Liturgy Solutions is to help church musicians proclaim the appointed pericopes of the day that are normally sung. The Lutheran Divine Service is very flexible, and so the particular propers used from parish to parish vary. Some congregations use the appointed Introit to begin the Entrance Rite, others sing an Entrance Hymn instead, and still others sing the Psalm of the Day at that point. Similarly, between the first reading and the Epistle, some sing the Psalm of the Day, others sing the appointed Gradual. Some parishes use the appointed Verse before the Gospel; others use the setting in the service book provided as an alternative, in effect making the Verse an "ordinary" instead of a "proper". Then there is the Hymn of the Day, sung by the congregation. In Lutheran circles, this hymn is appointed and so in a way is one of our "propers". Hence, it is more likely to receive special treatment by the choir, and so we offer hymn stanzas to support that practice.
Most parishes establish a certain pattern about all this. Either the choir is in the habit of singing the Verse or they aren't. The do hymn stanzas or they don't. The Psalm of the Day is used or it is not. Some others, including mine, vary the practice. Some Sundays a choir singing the Verse of the Day, some Sundays the congregation sings what is in the hymnal. We usually sing the Psalm of the Day, but sometimes the choir sings a Gradual. And there about seven different ways we sing the Psalm, so there is variety there as well.
Whatever your custom is, summer usually means a break for your choir. Even where there is a summer choir, it is often a different, smaller group and so a different approach is needed. In places where there is a strict pattern for when the choir sings and when they don't, summer provides an opportunity to do something different. Congregations - and musicians - are more accepting of doing something different because of the season, especially if it is a simple variation. The advantages of this are two-fold: one can readily find something accessible for your musicians (who are fewer and rehearse less in the summer) and the congregation can learn through experience that the pattern of worship is about the Word, not when "it's time for the choir to sing."
Here are a couple of examples. In a place where the choir doesn't take stanzas on the Hymn of the Day, have a summer quartet sing a stanza or two each week using a simple SATB setting such as found in TLH. It'll be easy to put together, and the congregation can readily understand that "they're not doing an anthem because it is summer." (grin) As the people become accustomed to the blessing of this practice, you might continue it on occasion in the fall with your full choir, using a Bach chorale for a stanza on Reformation Sunday or even a creative setting from Liturgy Solutions. (Had to get that in there!)
Or maybe you are in a place where the Psalm is always chanted, and you have no choir for the summer. Once a month, the Psalm could be done instead in a song setting by soloist, with the congregation singing a refrain. Again, since there is no "anthem from the choir", people will be more accepting of this in the summertime. And, once they experience the blessing of the practice, they will be ready to have the psalm sung this way on occasion during the year.
What do you do with your propers in the summer?