If you have not done so, you may want to read some of the things written by those in the Wisconsin Synod who are working on the next hymnal for that denomination. There is much to consider. Far from being simply about which hymns to include, they talk about the whole idea of the congregational song. What is being sung and what is not being sung are important enough but what they need to sing, what they should be singing may be an even more important questions. Of course, we have a history of pastoral concern for the piety of the people. That was, indeed, Luther's concern and it was reflected in a rather conservative view toward liturgical reform. Yet, when it came to hymns, Luther was not conservative. He was somewhat radical -- not radical in the sense of what was sung but radical in the sense that the songs mattered, that they taught the faith and gave witness to it. As a result, the Reformation was as much sung into the hearts of people as preached. His liturgical reform was slow and deliberate but his hymnological efforts and those of his peers proceeded at a fairly brisk pace.
Robin Leaver has suggested that Luther's heirs may have given short shrift to Luther's original purpose in singing hymns. I fear he is exactly right. We have focused more on what people want to sing, what hymns they find meaningful and moving, what hymns express their response to God, what hymns stick with them after they left the building. But have we forsaken the catechetical, didactic, and confessional purposes for the singer's spiritual experience of singing? Ask Lutherans which hymns are their favorites and you will find a diverse array of songs -- many of which [most of which?] are not found in any Lutheran hymnals. Instead, the songs enter the mind and heart through ear buds from playlists formed by people who are singing as much about their religious experience as about God Himself.
Just as music has become entertainment styled to individual preference and taste, the church's song has also been subject to the same kinds of preferences and taste. Hymnals were once simply the domain of churches and their publishing houses but now they are thoroughly beyond the control and scope of the church. The music used in worship is as much the domain of individual artists and the distribution vehicle of the media as it is anything else. Even in liturgical churches, the music of the service comes from these sources rather than the official channels and even when the hymns and songs of the liturgical assembly are from hymnals and official churchly sources, that does not mean this is what the people hum on their way out the door.
Where once the prospect of a hymnal was somewhat straight forward and there was a high expectation that what was published would not only find its way into the pews but into the heads and hearts of the people in those pews, now it is much more complicated and there is no assurance that the book will be bought, or if purchased, used. So the domain of the hymnal publisher has become a mine field. There are many publishers and many hymnals but even more song writers and venues through which they promote their music. It must be asked by those who invest in a hymnal publishing venture whether or not the work will be justified or whether it will be the last effort. So, it at the very least, we must do better than simply give people what they want. We must give them what they need, what the church needs, what the faith needs, and help them come to see not only what they want to sing but what they should be singing.