Gutenberg blocks give you many options for creating layouts for your pages and posts. And you have a lot of flexibility with those layouts. You can group blocks together and create a reusable block of the group. It can then be used on multiple pages of the site or can be imported to other sites. Plugin developers, like Stackable and Qubely, are making the most of this feature by designing blocks that can be easily added and edited to sites. Gutenberg Hub is a project to provide easily importable layouts including the CSS.
Whether you design the layout yourself or use designs created by others, Gutenberg blocks allow you to build out your site efficiently.