Hi Tristan,
I gave up setup on MariaDB and divided it into two parts. One is back on SQLite for sensors with values I need on a short term basis and “long terms sensors values”, which I save in InfluxDB.
The backup is now on google cloud GitHub - sabeechen/hassio-google-drive-backup: Automatically create and sync Home Assistant backups into Google Drive
I created own Google API credentials. Now I’m happy with good database performance and stable backup.
Hope it helps in your setup.
Cheers
Peter