Hi Mark,
Several years ago I worked on a project that focused on a user-portal aspect and used this plugin:
https://wp-client.com
Unfortunately, the owner shut the company down due to some personal reasons, so I never got to finish the project or really dig into the details of the plugin. It worked fairly well, but I hesitate to recommend it too strongly due to the lack of long-term experience with it. It is focused on being a portal, though, and collecting files and such.
But, if you intend to do other ‘membership’ related projects (the portal thing kind of falls into that), I’d highly recommend looking into MemberPress, as it would be a better foundation, IMO, to learn. I suppose it would be a bit more setup work for each user, as you’d have to create a page for them and then set the rules, but it’s doable. (WP Client auto-creates the page/rules for each user.)
https://memberpress.com
You can also use shortcodes to control what content gets displayed to what users with it (on a shared, or even public page). But, there are also a bunch of add-ons that might make that kind of control more user-friendly… but I’ve never looked into this aspect of it.
Regards,
-Steve