We have been testing this on and off for a while. Faster motors with less gearing? - #5 has some thoughts and there is a Merge Request (a bit old) with the physical gears. The gears will not fit physically between the motor lugs for reversed ratio of 1:2, but you can get to 1:1.25 from 2:1.
Faster gearing on the z-axis is a problem for autofocus, but @JohemianKnapsody has been using faster xy successfully. I don’t actually know which ratio.