I wish that they would let AI audiences have a night to choose the songs for the contestants. That would be an interesting theme night. I think we would do a better job than them sometimes. :)
I was thinking the same thing. They could set up different boards for each one. They could take suggestions for 24 hours then close that board and see what duplicate suggestions they get for that person. Then post the duplicates and have people vote for the one they thing the person should do.
That should narrow it down to the one song.