This list excludes Flute in the Thunder V1 and FitT x TFotS x Temple x Swamp Secrets.

This list is based on my own opinion.

Ranking by quality:

1st Flute in the Thunder (additional points for being old) [1st in difficulty]

2nd Halloween March [6th in difficulty]

3rd Blue Clouds [5th in difficulty]

4th Underground Anger [2nd in difficulty]

5th Peaceful Night [8th in difficulty]

6th Rise Dream [3rd in difficulty]

7th Temple [4th in difficulty]

8th Fly High [9th in difficulty]

9th Random Music 1 [7th in difficulty]