If you have RSI you’d actually be better off learning to type lightly on the MacBook keyboard. Mechanical switches are making your poor ergonomic behavior less painful but the fix is to train yourself to type with less downward force.
Alternatively you could also try tactiles and the lightest springs you can tolerate and learn to not bottom out while still actuating the switch.
Using mechanical switches and caps lock for control is better for me, but indeed, stretching for frequent modifiers is bad.