I too have no desire to CNC, but would like some assist with the z-axis.
I am thinking of putting a stepper motor on the z-axis and control it with a stepper motor pulse generator that I either build or buy (check ebay). I want to be able to disengage the stepper motor so I can do fine positional movements manually, then reengage the stepper (probably with a lever assy of some sort) for large movements like tool changes.
If I get really ambitious, I'm thinking of converting the z-axis to a 3/4" or 1" ballscrew to get rid of the excess backlash. I'm thinking the larger screw will reduce/prevent flex in the screw as it's floating on one end?
Or I may just counterweight the head with 50lbs or so of iron and stay with the manual handwheel.
Bill