What a cool thread! I like how you put the specifics of your workflow and especially details of the commands you used! Particularly with the vamp commands, because as you say, they are somewhat inscrutably named/documented.

I started dabbling with vamp as well a couple years ago, but lost track of the project as my goals started ballooning. Although the code is still sitting (somewhere), waiting to be resuscitated.

I have had an idea for many years of the utility of having chord analysis further built out such that a functional chart can be made from it. With vamp most of/all the ingredients are there. I think that's probably what chordify.com does, but they clearly haven't solved segmentation or time to musical time, as their charts are terrible. I don't think they are using chordino, and whatever they do use is actually worse.

I got as far as creating a python script which would convert audio files in a directory into different midi files, to start to collect the necessary data to construct a chart.

For your use case, you'd probably just need to quantize the chords to the nearest beat, so you could maybe use:

vamp-aubio_aubiotempo_beats, or vamp-plugins_qm-barbeattracker_bars

and then combine those values with the actual time values that you are getting from chordino.

I'd love to talk about this more, as this is a seemingly niche area. I've only heard about this rarely if at all, so I was happy to read this!