The Z Value would be equal to the rise per move.
The Z value in absolute mode, G90, would be where you want the tool to end at.
The Z value in incremental mode ,G91, it would be how far you want the tool to move.
Normally, you do not program "rise per radian", you program rise or fall per move.
Your "Option 2" would be equivalent to "rise per revolution".
P.S to emckell,
A radian is the angle at which the length of the arc equals the RADIUS of the arc.
1 radian = 180/pi = 57 deg 17' 44.806" = 57.29577951 degrees
ObrienDave. MasterCam since V6. Gcode since 1983.
The nose you punch today may belong to the butt you have to kiss tomorrow.