Ask HN: Best way to experiment with text text editing?

A few hours ago I commented in a thread that it irks me how we 'put up' with all the bad initial ux and quirks of editors like vim simply because nobody has improved over its big feature (modal editing).

Thinking about it, I'm wondering: What would be the best way to start tackling this problem?

To clarify, I don't want to deal with rewriting the hundreds of features that real life editors have to handle, from file management through text encodings to syntax highlighting. Those are completely ortogonal to the problem I'd like to tackle, which is the interaction itself.

I want to start with some sort of baseline with all those features covered, on top of which to build experimental interactions and see what novel or improved ideas I can come up with.

Should I fork a project like vscode and start there? use a simpler minimalistic non-mainstream alternative? learn emacs in depth and use that as a baseline?