I also agree it is a good idea to give control to the user to choose
- How to expand : between “breadth-first” and “depth-first”
- Then, how to filter : using dynamic keywords/references
This is what I’ve been telling people all day long these days. It is not an either/or. Good UX design (I like the citations system in your result!) can take the best of both words: The classic search engine (or any other classic UI), and AI functions/conversational UI.
The business model is unclear, but you are definitely into something here.
Good luck !