I'm still looking for a good solution for nested blocks. Neither the new layouts nor the area splitter extension is exactly what I need.
As you can see in the simplyfied attachment I want to insert a block "highlights".
Into that block I want to insert an undefined number of nested blocks (content or video or custom blocks etc.).
By changing the design of "highlights" the look of the inner blocks should change.
And "highlights" with all its content blocks should be copyable into scrapbooks.
Any idea or help?