I was surprised to see an organization that I esteem promoting a conference on the need for excellence in worship that emphasizes music and aesthetics, featuring a hymn sing.
I don't think anyone is for bad singing, bad lighting, casual dressing, slovenly grooming, or doing anything poorly in worship. But the excellence of NT worship is especially in heaven, and this is communicated by a simplicity on earth that says, "the great Excellence is in glory."
In other words, "more outwardly attractive" is not the same as "more excellent," when God Himself has set for us the aesthetic of simplicity. NT worship is to be excellently simple in the congregation on earth.