I’ve loved this tool. One feature I would love to see: all keys in the “Transposing Instrument” section.

Reason is I play harmonica. If we are using a diatonic harmonica, we may select a different key harmonica depending on how the melody would lay on the instrument.

Currently we don’t have all keys in the transposing instrument feature. However, if it were enabled, then I could, for example, use a harmonica in the key of A or Db without having to transpose at sight.