I came out of the mechanical keyboard rabbit hole with multiple Leopold FC660C Topre switches (there's no going back to any mechanical switch) and Hasu replacement controllers that support QMK.

Here's an out-of-date version of my layout, heavily using tap-hold to access multiple layers:

https://raw.githubusercontent.com/Syzygies/log_folders/maste...

Chording never took for me, but one-finger-each-hand concentrated near home row is such an obvious way to quadratically expand the address space. The Matias space bar was certainly an inspiration for this, though everyone uses QMK tap-hold for purposes like this.