i built and used this Dactyl for 3 years... printed custom keys for the thumb-cluster after some days and that was a **great** upgrade! however i think apart from the blue (GREAT) and green (good), you'll have difficulties to access other keys! unless you have no wrist and arm rest at your table/chair, as that frees your arm to move your hands by your shoulder/elbows, allowing a much broader range than using your wrists only. i used this way and i would say i made my way to heal my wrists on these 3 years of usage. probably they didn't get into the way, as i think stretches and exercises and much more relevant for RSI correction than keyboards. before i was in a laptop keyboard with a far from ideal ergonomic setup on my bedroom, working full time on computers

after my dactyl build, i started selling keyboards on my free time and after dozen of keyboards made (tried all designs of
https://ryanis.cool/cosmos/beta and a bunch of other flat ones) and i would say this last photo (keyboard on a green pad) is the best layout you'll ever try. this time with green keys being the most comfortable and blue ones following right after. the outer keys i still have no idea what function to place, even after a year with the keyboard
