I've started making use of the ability to create my own blog templates for clients then allow them to select them when creating a blog post.
One thing i would like to see added to this is the ability to add a class name to a block if possible (and this might work for blocks on the page in general using Composer). This would allow us to not only create a structure for a blog post which can be easily used but also to then easily style the blocks within that structure?