Don't forget Cultivar
I get 90% of my coffee from a family friend with a small roastery. He travels to individual farms and selects the specific varietals (naturally occurring sub-species for that terroir) or cultivars (transplanted sub-species that would not normally grow there) that he finds especially nice and brings them back to roast.
He then markets them with names such as "Finca Esperanza, Columbia, Pink Bourbon" or "Fazenda Pico Agudo, Brazil, Yellow Catuai".
It would be refreshing to have such transparency and consistency across the board so you know what your getting. While I enjoy trying lots of different things, it's nice knowing when I pick up a pound from Okon, I'm getting a Colombian Pink Bourbon from the Esperanza Estate, or a Brazilian Yellow Catuai from the Pico Agudo Farm. Knowing the farm is like knowing the vineyard where your wines grapes were grown, but generally the vineyard and the vintner are one in the same. Not all that typical that the farmers are known as world class roasters...
I see this as being the best identifier of what you're getting. Second to this would be as you point out simply knowing the varietal and location. It's like the difference between visiting a farmer's market where you select your produce from each farmer versus a nice supermarket where you can select different varieties of tomatoes from Canada or Mexico. What we normally have with coffee is somehow knowing it's Canadian or Mexican tomatoes without knowing whether they are Heirloom, Roma, or cherry tomatoes...
I wonder how the details get lost. Surely the farmers know what they're growing, right? I suppose I could see a broker gathering up various Colombian Bourbons and mixing them to have enough volume for a large commercial customer, but how do the Bourbons get mixed with the Catuai and the Typica? It may just be an issue of demand. Hell, some folks might just assume that Juan Valdez goes around with Conchita picking all the fresh coffee grounds in Columbia to make those delicious cans of 100% Colombian coffee. If the customer doesn't care, I suppose whatever is available right now reigns king and the country of origin is all that gets noticed or even recorded.
Anyway, I agree that it would be nice to settle on a nomenclature that gave better info, but until customers demand it, I suspect only the very high-end stuff will retain its pedigree, because who wants to know the bloodline of a mutt?