A prompt, or more like a list of them seems the most interesting customization. For example: "no crypto currency", "nothing from Keith Rupert Murdoch", "chinese realestate", "ukraine war", "forex" etc

Now that would be worth something...

Say, you want more than 6 filters they costs 50 cents/filter/month with a minimum of 5.

I think one would gradually make more and more of them?