Hi,
at the moment i am using ACF Pro with flexible content field as a “page builder”. This works okay, but on long pages it becomes confusing for the client.
I have seen the Type Rocket PageBuilder:
https://typerocket.com/docs/v3/builder/
It’s nothing more than a flexible-content, but with an other UI in the WP backend.
One list on the left (with thumbnail-images) that shows the page structure and the fields of one “row” on the right.
I am not that into coding WP plugins, so i think it is not possible for me to code something like that as an addon for ACF. But maybe someone thinks this is interesting, too?
There have actually been several people that have attempted this. I don’t know what the results were. If you search the forum you might find some of the topics.