This is an interesting project for sure (writing text editors are fun, and the mix of technologies chosen is interesting) - but I think it would be fairly straightforward to implement the features you've shown in your demonstration as an emacs package :)
Emacs has a ton of baggage. I like the fresh approach and especially the idea of hacking on my editor in go. As a hardened vim user I like that influence and I think it shows in edi.
