I don’t have a lot of experience with what you’re describing. I wonder if it would be better to have the collections associated to the artifacts (media) instead refer to links? These links would be the urls of the s3 assets.
So, for example, if you wanted Blogs to contain “banner-image”, instead of banner-image being a relational attribute to a media object, it would be a text attribute (url to the media object).
Not sure if that fits in your use-case or not