Gather herbs for merchant alliance ! {voyage idea}

I've been thinking about new voyages for the merchant to make it more diverse. An idea came to my mind. So if we have such things as crates of cannonballs or bananas etc that we can fill up and sell AND we have crates of tea and spices, why not make voyages that would require specific types of herbs/spices. You would get an instruction on how the herb looks, and maybe even an illustration, you would gather a crate from the merchant. Then sail to an island and examine different plants in search for the ones you need, gather and put into crates. It would encourage exploration. Oh and make it worth, since I believe spices and herbs were of great value during those times.