I am a fairly competent (110+ wpm) typist, across a few different layouts (mostly qwerty/qwertz). I don't do this kind of deep customization for the same reason I don't use many plugins in vim or a browser: It would render me completely useless on 99.999999999% of the other terminals out there. I have a few different laptops, a desktop, and even with total control of those devices, I still end up on other people's hardware.

If you have medical reasons, I mean, I guess it's better than nothing, but this reads to me like the computing equivalent of moving into the woods and becoming a hermit.