What fruit trees/bushes would you purchase as a homeowner?

I’m an individual with a forestry/horticulture background, trying to make some extra money before my body breaks down, and am looking for advice on which plants the market may not yet be saturated with.

I haven’t seen a single person within driving distance selling pawpaw, elderberry, or persimmon, with many people selling blackberry, strawberry, and passionflower plants.

I am of the mindset that, if you’re going to put time and energy into plants, they need to produce something you can use.

Outside of STL in zone 6.