This sounds to me like a perfect use of Advanced Custom Fields “flexible content” feature to me. Flexible content fields allow you to define multiple layouts, and then add them to a page or post one by one, in any order or combination you need. Each layout can be a combination of text fields, images, wysiwyg editors, and other field types.
It’s a brilliant UI on the client side, and easy to build a custom front-end in your template once you get the hang of it.
It’s a premium plugin, but I’ve been building these kinds of interfaces for many years and it works really well. I haven’t found anything else quite like it.