I love the esoteric-ness of owning a Kei truck, but they are in no way a replacement for a regular pickup truck. You really need a separate car for dailying, unless you never drive anywhere other than around your farm.
Yeah, I'm not sure how owning (and maintaining/registering/insuring/inspecting) another barely roadworthy vehicle competes with just having a trailer or renting a vehicle from Home Depot for a few hours now and then.
For just moving stuff around the farm my neighbors have basically electric golf carts.