I have not! Truthfully I've been hella busy with my day job and other ventures (and also am still waiting on a bit of art before I drop 0.14) - The big thing that's taking a while is I've probably scrapped and reiterated the formatting for how I want to handle data packs 2 or 3 by this point (especially in the map department) - Namely because I'm trying to figure out what utility they serve and the kind of game I want this to be (and ironically I'm finding story and map data will probably be wildly more useful than enemy data, so I want to really get that right in the same way the mechanic shop was).
For some inside baseball: In many ways Steel Hearts is house rules designed to run for bespoke campaigns customized for each table down to the enemies. As a result it's kind of tricky to release general purpose enemies and content when the best experience you'll get as a GM would be something custom tailored to your players ((and worse yet, I don't want to release a data pack that accidentally puts a GM in a position where they wipe a party due to mismatched expectations of the system and how to use a data pack etc)). However I would really like to add a whole bunch of enemies, so I may fully abandon the idea of "threat levels" and simply say "Here's a bunch of enemies that I've run in the past, how I stated them out, what they were used for" etc with the very big caveat that GMs will need to custom tailor stuff for their play groups instead of expecting enemies to work out of the box with an easy way to tell if your party is ready for it. It's simply not that type of game considering how wide the build variety can get, and how much player strategy and gameplay "skill" can turn an impossible scenario into a trivial one and vice versa.
Steel Hearts Zero was always about getting all the player functionality done, (relatively) polished and out in the wild so that I can tell people who want to use the system (re; many of my friends and colleagues who wanted to and ended up running it) that all the player stuff is readily available! ... How the GM stuff aught to manifest is still a mystery to me because it needs to feel like something I would personally use, otherwise I'm stuck tailoring to an audience I don't understand which is a lose for all involved.
What I should do is write another big update about all the stuff I've been tinkering with, buuuuut that'll probably wait til February when that sweet sweet cover art is done.