QMK itself is great, but I was never able to find a non-columnar split ISO keyboard to use it with. Eventually I reluctantly settled on the Logitech K860[2] and I'm now happily using my favourite features from QMK with kanata at the software level.
[1]: https://github.com/jtroo/kanata
[2]: If I'm behind the times and there is now a QMK-compatible keyboard that looks like this, please let me know!