Nice blog post. If you're aiming for a comprehensive run down of tools, I suggest including wal-g. We've been using it since it was released (and its predecessor wal-e for years before that) and it's been great. We currently use it to back up a replica to S3, and it has no issues doing that. In more recent versions, it supports delta backups, which decrease the time/load required for a backup immensely in our case.