I think making it a community driven project, either run by miners charging fees, or some other concensus, would make more sense, or building it on ethereum/another ecosystem and charging fees.

In terms of other services out there, they require drivers to be vetted before the are eligible to deliver food/packages, and users have to provide their phone number and email, which eliminates the focus on privacy I would be aiming for, and means not just anyone can sign up and become a courier.

Also, similar to the issue with most banks, delivery systems in developing countries are much slower on average and many people don't have access to those types of companies, partially because those companies are focused on making a profit/branding etc and can't operate in a truly decentralised manner because of their business models.