Alright. Here's my suggestion for you, Kon can come and double check these for the Final Approval.
Dance of the Willow This should be a D rank simply because of what all it entailsl. It's the most basic of the dances.
Dance of the Camellia C Rank
Dance of the Larch This should also be a C due to the fact its only something that can be used as a counter attack and its power is varied based on the power of your opponent.
Ten-Finger Drilling Bullets B Rank
Dance of the Clematis: Vine This is the first half of the Clematis Dance, and all in all is just a stepping stone to the next part. B Rank.
Dance of the Clematis: Flower A Rank
Dance of the Seedling Fern Is most certainly S Ranked. Don't forget that this one, unlike the rest of the Dances, is actually Ninjutsu.