Disclosure: I work on Google Cloud. Apologies if you find this to be in poor taste, but GCS directly supports the S3 XML API (including v4): https://cloud.google.com/storage/docs/interoperability and has easy to use multi-regional support at a fraction of the cost of what it would take on AWS. I directly point my NAS box at home to GCS instead of S3 (sadly having to modify the little PHP client code to point it to st…
Just saying, it gets you a foot in the door.