In reply to Godwin:
Rickshaws are essentially human powered taxis. Any ethical considerations would only relate to fair pay and working conditions.
As with any heavy human powered vehicle, hills are the enemy. How hard or easy it is physically will depend on the terrain.
Electrically assisted, human powered delivery is becoming more and more a thing in U.K. cities and not just deliveroo. I can see a market opening as cities, rightly, rebalance space away from motor vehicles.