I finished this project a while ago but forgot to share it on the list.
[sketch] is a tool for drawing polygons and Bezier curves into arrays, very useful for creating envelopes and custom waveforms. It's easy to use and state-saves automatically. Take a look at the attached gif to see.
You can find [sketch] in the Context library:
https://github.com/LGoodacre/context-sequencer https://github.com/LGoodacre/context-sequencer
It requires several externals.
I hope someone finds it useful!