Are you familiar with Overtone[1]? I'm no musician, but as a developer I'd think building your own musical abstractions via code would be better than any visual IDE.
https://www.youtube.com/watch?v=xJZyXqJ6nog
https://docs.blender.org/manual/en/dev/editors/python_consol...
[0] https://vimeo.com/36579366 (circa 3 min. mark)
On the other hand, there are vector graphics editors that let you work in terms of shapes and paths instead of pixels. Would you say you are trying to build the musical equivalent of that?
[1] https://www.infoq.com/presentations/music-functional-languag...