A simple idea with wonderful execution!
I've been using Liftoff (https://github.com/postlight/liftoff) with Airtable as a DIY solution for this and while it's been easy to set it up and deploy it on Netlify, I still had to resort to writing a custom watch for changes daemon and forking the repo for adjusting the components layout.
I like that SheetUI has the things above built-in and more functionalities like adding buttons and a customisation UI.