As a recent member to the community I have been investigating HASS for suitability not just for my home automation but for use in a solution for others. The frontend GUI is great. But the thought of editing config files just makes me want to barf (sorry for the candidness). I’m a software engineer and days of editing xml files are torturous. yaml is a bit better but its still the same effect. I get that using yaml files in the beginning allowed development to focus on other more important aspects of the system. But if this system is to grow this is thing that has to change. Saying that it is a one time thing is not correct, as you may add new automation rules or add new switches etc and it overlooks the main pain point, ie. that it is not easy to use.
In comparison, Openhab has habmin, an addon UI that simply allows you to edit openhab configurations in the browser. This would be similar to using the ACE Editor as proposed above. This could be a MVP, but it still relies on yaml in the back which may not suit if the end goal is somewhere else. The newer Openhab 2 also has a new Habmin 2 interface (github.com/openhab/org.openhab.ui.habmin). One of the big differences is the addition of a graphical rules editor
Conrad connect takes this to another level with a nodered https://nodered.org/ style configuration and saved IFFT style recipes that you can add and edit with just a few clicks. It looks amazing.
Configuring devices and adding automation rules are the clunkiest thing with most open source home automation systems and if HASS is to grow, this is the one area that needs to evolve. (note the absence of config files with commercial products)
There does however appear to be some serious technical obstacles as mentioned above such as reloading configuration vs restarting HASS and creating GUI’s for hierachical configuration files. Note that Openhab automatically reloads updated config files, but still uses convoluted config files. Also worth thinking about is that if there was a config gui, there may be less support for people having configuration issues.
Sorry for the continued references to openhab, its just been something that I’ve been looking into recently. Openhab has some nice points, but also a lot of negatives as well (its using 10x the ram in my test environment)