Yeah ridga or vzhextrudort style gears definitely help greatly. You could do a mihai style test to see if the artifacts on the i3 are mostly extruder related or from the XY motors.

Tuning drivers consistently for quality is going to require an oscilloscope, although there are some experiments with attaching an accelerator to the motor while doing a frequency sweep.

Of course you could just change settings and see if there is a visual difference, but there are too many settings and combinations to make that realistic.