I've always liked umlet and umletino (web version) for a nice mix of drag and drop and edit by text editor. In the absence of good enough layout algorithms, the ability to manually drag things to the right place is kind of essential. The resulting diagrams are not so pretty of course.

I have tried a lot of tools in this space. If it comes out looking alright, that's usually because it was so simple that it didn't actually need a diagram. Anything with a bit of non trivial structure seems to quickly escalate with essentially no good options other then esoteric hacks with styling to make it look any good.

This seems to be a thing where you can have pretty automated layouts, complex diagrams, or correct diagrams and can only have two out of three.

Which means that almost 100% of my use cases for these tools never really work for me unless I sit down and grab some old school drawing tool (or just give up on the whole notion, which is much more likely). If it was trivial, I wouldn't bother making a diagram. These tools seem only usable for stuff where diagrams were overkill to begin with. I saw no examples on the linked article (and the rest of the site; I browsed the top few recent articles) to really counter this.