[dcherba]

To engineer this properly you need to determine the torque needed to hold the arm in position. Then factor in the gear box and determine the torque required by the motor. Assuming the motor is stalled use this current and the resistance to determine the total watts to hold this in place. Compare this to a conservative continous rating of the motor. The motor is not turning so it doesnt have the fan running to help cool it. So a motor that can deliver 300 watts peak might have a 100 watt continous rating and a conservative rating might be as low as 20 watts.
For a FP motor you might be limited to under 2.0 amps or less as a holding current. The answer is more gear ratio lower holding current.

All the stuff about the electronic brake and regen just helps with controlability when the arm is being lowered and keeps it from running too fast when the speed is set to zero.