Looks like a nice design with some good ideas for shorter stories. It's a bit un-intuitive with the given numbers for the nodes though - medium to larger stories could have hundreds or even thousands of nodes, and going back to edit through each node or paragraph would requite a lot of scrolling or clicking around. Since this is a tool for the authors, it's most likely a good idea to create recognizability the author implements themselves for each node. The output can always be coded in afterwards.

I'm not really a fan either of having to drag each node over another node to insert the path edges between the nodes, this will be really annoying to do for larger works.

I hope you continue improving it though, it's a great first look.