I love that transition. The first time I heard Iridescent I instantly thought, "They should play this after Numb. The piano transition would be wonderful." Prior to that, I didn't think there would be anything that would make me want Numb to stay in the setlist.
But anyways, maybe they could play the Wisdom, Justice, and Love sample over the piano transition since WJL is just that speech sample over some piano. It could actually work quite nicely. Though I really think they should bring back the Just Like Heaven cover over the piano outro to be honest.