I’m thinking that it’s an information store that reacts to input from the user, like I say I may be off the mark and I may need to have something coded. I have a habit of trying to do things with things that aren’t really designed for the purpose
For example I create a form per topic with banks of possible outputs in each topic. If the user selects ‘theme’, this triggers 1 random selection from a bank of say 50 phrases to be displayed. I would have multiple instances with different topics, idea being that someone can then have a selection of randomised topics to put together as a creative tool.
I was looking at things a little like this https://www.plot-generator.org.uk - feel like I can do this with Gravity Forms but I wasn’t sure about the display of random elements. Also Portent's Content Idea Generator - Instant Blog Topic Inspiration - there is an input that then displays a randomised output of a bank of phrases, based on what the user enters.