Ultimately, the litmus test of congregational songs is not the style in which they are formatted; it is the content they are presenting. If our conversation about church music remains simply of style, we have not lifted our attention high enough to what is of first importance. The songs of the church should blatantly remind and retell the story of the gospel of Christ (1 Cor. 15:1, Psalm 105:1-5). In this, God is glorified and the church built up in its faith.
At my church, Calvary Memorial of Oak Park, we on the worship arts staff make a point to examine the text of any song we use in our corporate worship services. We look for what my music minister calls "the creedal statements," and we also use songs that repeat certain phrases that simply declare truths. Last weekend, for example, we used "Praise to the Lord" ("Praise to the Lord who o'er all things so wondrously reigneth") and "Good to Me" ("For You are good / For You are good / For You are good to me"). But for any choice, the text must be based in gospel truth - as Boswell notes elsewhere in this piece.
Ideally, in any given worship service, the entire story of the gospel of the grace of God will be sung. There is a wealth of songs, those written recently and those written centuries ago, suited to this task.