ss88us
Why don't you build a Backup server dedicated, can be on a separate server or even in a different DC? (Enhance was built to work like that) I am using this and I have no issues.
I back up 2 production servers on 1 backup server and the 2 servers are on different DC one in Sydney and one in Brisbane, also Backup server is in a 3rd Datacentre.
If you can not afford (or not suitable) another full server, you can use a VPS, these guys sell them cheap (supposed to work well in the EU) (much cheaper compared to S3)
https://www.time4vps.com/storage-vps/
I see this as a good solution, especially if Server disaster recovery will be working (let's hope very soon).
As a note I figured out that if we could filter backups according to the server they were backed up from, and select all in 1 click, when the hardware gets faulty, (after Hardware is repaired by DC) install in a few minutes enhance and from backup server select all accounts that were on that server and click Restore. This would be a great feature.