The sensor is a reasonable long term solution. Setting your mixture by long term performance (plug condition, fuel consumption), might actually work if adjustments were quantifiable. The clicks on the idle mixture compensator might be such, but MAP sensor adjustments are way too sensitive to be approached that way.
It should be done properly at least once to establish a base line.
This engine does have some inherent idle vibration (more so than later v8s). I haven't seen a propensity to poor idling due to valve lash on these but the valves should be properly adjusted. Having valves too tight allows some leakage of compression and disturbance of volumetric air flow.
Bosch Master, ASE Master, L1
33 years MB technician