I'm not convinced this is worth the effort. I assume that typing speed is rarely an issue for touch typists. It is also not clear that different layouts do help with RSI.

But the main issue for me is having to switch between layouts. Actually, it's an issue I used to have living in France, where I occasionally had to switch between my QWERTY layout and some AZERTY layout (for instance, to show something to a colleague and friend). Even though I know both layout, there is always some adaptation time.

Slightly unrelated, I noticed that what breaks my typing flow is to add/remove pairs parenthesis/braces (which happens all the time when coding). I still haven't found a good solution to this. I think that even Vim doesn't have a good default solution for this. I wonder how efficient typers solve this issue.