weights and measures

My thoughts on the most logical units of weights and measures. The goal here is to have intuitive, easily understood units.

The length and weight units would be equal to the height and weight of the average adult human.

The unit of liquid measure would be equal to the bladder capacity of the average adult human.

But there is a problem here. The size of people varies from culture to culture and from century to century.

The unit of currency might be equal to one day's wages for the least-skilled, lowest-paid workers within the culture, if I'm creating units for use within one culture. There is so much variation in pay scales around the world that such a unit would not make sense on a worldwide basis. Indeed, there are still a few cultures that live close to nature and don't have the phenomenon of paid employment, lucky devils.

Still contemplating units of light intensity and sound intensity. Something like the old candlepower might make sense, or perhaps the brightness of sunlight at noon on a clear day would be the basis. For loudness, I think the regular speaking voice of the average adult human would be the reference point.