Modelling flexible content sections and recommendations A little background first; I'm coming from WordPress, along with the Advanced custom fields (ACF) plugin, so my thinking behind this may not be the best way in Craft. 

In ACF I usually set up a field set that consists of an outer repeater field, with a nested flexible content field inside (much like the Matrix field in Craft). Within the repeat field, there are a couple of options that controls the appearance of a section, such as a background colour/image. This is also used in my template to differentiate where a &lt;section&gt; starts and ends, and often has styles associated to style the overall section. Anything within the flexible content fields is contained within this.

Then, within the flexible content field, I define my layout types (title block, two column text, text with image, etc.). An image to describe the layout structure if my description is a little confusing: 

I'm looking to create a similar sort of set up with Craft. Without an outer repeater field, I'm struggling to think how to achieve the "section" container. What would be a way to achieve this sort of thing?

Thanks!
I'm not familiar with ACF, but if you're looking for blocks-within-blocks, you could use the Neo plugin/fieldType. It allows you to define blocks, and then have nested blocks. It allows for decent management of blocks, too, so that you have children of specific parents. 

For example:
You could have the following blocks/content types:  


Copy
Card
Image slider
Form
Ad Unit
Related Content


And then the following layouts and components:  


Two-column
Three-column
Single column w/ Sidebar
Column
Sidebar


The Neo fieldType would allow you to make block groups, and then allow the content blocks to be limited to certain layout blocks. It would look like this (demo only, not fully configured):

The layouts are selectable at the top level. You need these to target template files (or at least it makes it easier, IMHO).  



The layouts can only have columns or sidebars. The two- and three-column only have columns, while the single has column and sidebar.  


  Note: Currently blocks are only limited on the page level and not the block level, meaning if you set the max number of columns to 1, you'll only be allowed one column per entry.  




The column block has the main content types, while the sidebar block has the sidebar content types.