Personally, I’m using Typora as an external editor when I need to edit tables with a lot of content in the cells. It’s simply the only editor I know that handles this task gracefully. (Yes, maybe Zettler too, but it’s not very convenient to use it as an external editor.)
One thing that you get only in Obsidian and in no other external editor is the whole experience around links ! If you enter a link in iA Writer or any other editor, you won’t get the interactive selection list, nor the possibility to interactively link to blocks or headers. And you won’t be able to drag and drop references into your note and get an immediate link.
Just a few reflections. I do think that Obsidian has got a more than decent editor. I dare to say it’s a great one, as it is right now.
Olivier :-{)