so this is a bit out there but what worked for me and really changed things was taking feldenkrais classes. I had a pile of weird ergonomic keyboards, did crazy stretches, exercised, and tried every keyboard layout but going to a feldenkrais class once a week changed my relationship to my body and stopped me from creating crazy tension any time something felt off.
this is where i found out about it: https://www.nytimes.com/2017/10/30/well/trying-the-feldenkra...