I'm an electro-mechanical engineer unfamiliar with small farms. How would you change this type of design to be more modular or adaptable?
In general, I think low cost, low maintenance, and the ability to repair it yourself (lots of COTS parts) are the main benefits.
Interchangeable buckets/attachments would be good. What I mean is that I see a lot of outdoor or primary sector uses in the existing carts. Could be good to have the bucket of the wheelbarrow be interchangeable for the secondary or value-add steps. Many small farms need to vertically integrate to survive. So maybe have it focused on processing, like hauling, warming, and bottling (honey gate) that 100 gallon container this honey device uses. Or maybe for hauling mushroom bags from sterilization, to inoculation, to fruiting rooms.
Also, I assume many of the people using a powered wheelbarrow type device would find a loading aide/mechanism highly beneficial. Stuff like shoveling takes a long time and can be hard on the back.