(1) Importing notes takes forever, I'm talking hours, even if you're pointing to a local notes folder.
(2) There is no background sync on mobile so every time it's open the app, wait a 10+ seconds to sync, then open the new note. I've found myself keeping important notes on Keep for quick access.
(3) All notes and resources are in a flat folder so if you have a large database filesystems will struggle and break in strange ways. I guess I hit some limits in OneDrive and it can't list all files so I started missing notes. I ended up doing an audit and found a couple dozen things not syncing. Now I'm paranoid I'll lose more notes and commit all changes to a git repo.
I still think there isn't a better alternative in my case and plan to make improvements to address my pain points.