Cool idea!

I've got a few thoughts for features, if you're open to them:

1. Ability to specify where your "played" voice resides in the voicing: As the bass note, as an inner voice, or as the top line.

2. Options for first species, second species, third, florid, etc counterpoint for each of the generated voices. Ex: You play a single note and the upper voice plays two notes for every one of yours, etc, etc.

3. If you want to get real fancy, make the generated voices perform a canon of your played notes.

Have you been able to try it as well would love to hear what you think! Coming back to the features, regarding 1. you can already choose between soprano, alto, tenor or bass. I have still filed an issue for this, will help me remember to take vet this feature. Sometimes it's not as strict as it should be but that's also something I need to work on. Regarding 2. it's a good idea, helps you be in control of the kind of counterpoint you are doing, filed an issue for the same. Please feel free to comment on the issue. 3. is just feels is a little goofy as well I love it. I haver filed an issue for this as well check https://github.com/contrapunk-audio/contrapunk/issues/