Fascinating! I'd really appreciate it if you could @ mention me when you finish dissecting your best-performing articles.

I've been out of that world for a good while now, but I hypothesize that you'll find that a lot of the most successful performing articles in your niche are "HOWTOs" on fairly basic topics. I'm guessing a lot of the Medium readers in those topics are either students or programmers looking to learn more about new languages/frameworks and are thus not likely to relate too much to advanced topics. This is just an off-the-top-of-my-head guess, though. It'd be interesting to see what you find.

Incidentally, I started off on Medium by trying to put in some academic rigour in my articles, including doing my own empirical analyses. Worked well in getting curated back when curation requirements were more stringent than they are now, but didn't justify the added effort in terms of views. People seem to expect you to read, understand, and digest all that material and repeat it in a rigorous yet accessible article.

Tough crowd! :)