There are a lot of companies who use Medusa in production, yes. Archiving to NFS is a good option and works in a lot of use cases. You'd just want to make sure that there's limited access to the backups so they can't be accidentally deleted or result in a security breach.
We would love to hear about any issues you're running into. And big +1 on submitting PRs. We're happy to help and you can reach the Medusa engineers/contributors directly on ASF slack <https://s.apache.org/slack-invite> in the #cassandra-medusa channel. Cheers!
