I’ve noticed in my journey from moving from Joomla and Invision Power to WordPress that its difficult to find applications that do what you do want the way you want to do them.
In my journey of finding a Document Management system for my wordpress site I do a lot of research and comparisons until I find the best solution for me needs and all of our needs are probably different so what I pick as my Document Management solution may not be the same as what would work for you.
Many websites I come across name WordPress Download Manager (WPDM) as a top contender. I like and dislike this application.
NOTE: I tested using version 4.9.3
I like the fact it comes with a TinyMCE plugin that allows you to insert files into your post that you uploaded to WPDM.
I also like that you can Attach a Directory or make a file available for a certain date range.
I like it has so many plugins that will work with so many other applications. It has so many options per file (or package as they like to call it)
Also I like that it looks like we may be able to organize (hopefully import) all our files in our WordPress Media bin.
I dislike that they reference files/documents all as packages. It confuses me. When I see package I instantly think of WooCommerce.