Hi, I really enjoyed your post! 
I have developed a python script around sqlite (with SQLAlchemy) to deal with this sort of changes; the idea is to export the sensor data into CSV, edit it with your favorite spreedsheet app, and import it back. This way I hope it would make it more accessible for people.
Do you mind taking a look at it? I'd really appreciate your feedback.
https://github.com/naevtamarkus/homeassistant-statistics-cli
Thanks!