The much easier solution is to reinstall Legacy until such time as the new version is robust. The very existence of Legacy says much about the community response to 10.x. From a dev. perspective this should have been a voluntary public beta. Forcing the upgrade was a massive fail. Maybe a MVP was confused with a viable product?
Reinstall 'Legacy' (see the thread). I'm with you, but legacy works fine. If they can't get feature equiv. with Legacy , then it will be time to move on. Right now OneNote is no harder to work with that 10.x - it's that bad.