I've always wanted the Shibutanis to skate to Yo-Yo Ma's "Sakura Sakura", a modern interpretation of a traditional Japanese folk song.

http://www.youtube.com/watch?v=SETNAh50DCI

The dynamics in the piece can show off their range, the song is quite different from what they skated in the past three seasons, and the song is 4:22 long so it's easy to edit. Most of all, it's different from what every other team does or would do.

I think the Shibutanis should go down the route of spiritual elegance, with programs that show off non-romantic beauty, the pure bond between sister and brother. Pieces like Meditation from Thais, which S/Z famously skated to, Chopin's Nocturne Op. 9 No. 2, or Clair de Lune are along those lines.