My dream is:

* Every user in the web interface gets a sql database user.

* A change in the database schema should reflect an instant change in the AP GUI.

A dream that I have worked towards step by step in a few different projects. I am not sure about how it scales to millions of users. But if you have a a few 100 to a thousand users. It should be fine. Main problem i have found is row level security. The app should basically just be a graphical interface that can be configured. Through a config file.