I would pay good money to Evernote if they had a "backup all my data multiple times, removing all possibilities of losing anything". I would gladly pay for Premium if that was an option.
All attachments added to Evernote are now stored redundantly in Google Cloud Storage, which is designed to do just that.
You should look at CloudHQ. Their PDF backups to e.g. Google Drive preserve everything out of Evernote. Used it once to get away from Evernote while still preserving search of old stuff.
Thanks. I don't want to get away from Evernote though.