I like your list too. I don't think Pat Boone counts himself a member of the church of Christ anymore. He left for a more charasmatic experience. His brother Nick is still around though. I'm not sure Amy Grant is a member anymore either. When she divorced Gary and married Vince, she said some things that led me to believe she had left the church. Her family, particulary her grandfather A.M. Burton, was very generous to the churches of Christ and Lipscomb during his lifetime and in his will.
Kenny Perry's wife went to Lipscomb. He gives 5% of all of his earnings to Lipscomb. Marty Roe went to Lipscomb too.
Last I heard, Amy Grant was attending Belmont Church in Nashville, which used to be a church of Christ, but that was years ago. I went there once when I was in college, and it was quite an experience.