I LOVE this.
All of the techniques that they are showing have already existed for awhile in places like Automatic1111/ComfyUI or its extensions (i.e. regional prompting, attention weights). Having it connect so seamlessly with rich text is awesome and is a cool UI trick that might make normies notice it.
Also, related, but NLP is extremely undertooled on the prompt engineering side. Most of the techniques here would work just fine on any LLM. If you don't believe me, read this: https://gist.github.com/Hellisotherpeople/45c619ee22aac6865c...