I am trying to create a secure document management and control platform for my site's membership, but it's less to do with selling access to content, and more to do with keeping documentation created by, or uploaded from, members safe. They need to be kept exclusively for member to upload, create or edit, but other members would have limited read-only access, via an account related security code. Some files would need to be able to be read by other members, via the account access code, while others would not even be visible and certainly not accessed.
Could anyone give me some idea of how I might be able to handle this using Gravity Forms or would you say, from what I have described so far, that is an application better suited to a membership site such as S2, Wishlist, the even the Gravity Forms "User Registration" plugin, or some other membership plugin, or perhaps even a combination of both a membership plugin and Gravity Forms. And if so, which membership plugin would you recommend to work better with Gravity Forms in this situation?