Allow us to specify S3 IAM Access Credentials as part of api requests
Right now, we have to grant read and write permissions on our buckets to your AWS Account. If someone were to compromise your AWS account credentials, they'd be able to access secure data stored in our buckets (very bad).
As an alternative, allow us to specify the AWS IAM Security Credentials that we want you to use to access our buckets as part of each API request. Since these would be passed to you as part of each request, there would be no need to store them on your servers so there would be very little risk of compromise. And if they were compromised, we'd simply have to rotate keys. Also, since these would be IAM accounts tied to our AWS account, there would be no need to share with you our AWS Canonical ID.