Aem Content fragments

I have a requirement on  designing Aem content fragment models & graphql endpoint for a mega menu. Where the menu items stored in content fragments currently. I am facing challenge with deeply nested fragment structure( Around 4-5 levels). I want to avoid this nested structure and the requirement is to use the content fragments.  Using json objects is also not suggestable because of business authoring.

Suggest the best way to solve this any new way of using CF.