As a thought exercise, where else would you put this resource type?
There are multiple ways to go about this. I am not opposed to adding another health resource if justified. But another alternative would be graphical variants of the same resource, by renaming Banana to something more generic like Fruit. Right now graphical variants for resources do not exist, but in principle that should easily be possible. I want to give this a try sometime.
I think variants for resources would be super interesting, and with fruits in particular what would be nice is that they can cover different areas of the map. Whether or not you'd like to implement them as graphical variants of the same resource or as different resources altogether, I don't know.
If we were to add fruits, here are some interesting things to consider
The most important groups of fruit worldwide, by tonnage (FAO data) are (in order): Banana and Plantain, Melons (watermelon, melon, cantaloupe), Citrus, Pommes (apple, pear), Grapes, Mangos and Guavas (always classified together, don't know why), Stone fruits (peach, plum, etc), Pineapples, Berries, Papaya, Dates, Avocados, Persimmon, Kiwi, Figs.
It would be interesting to have these groups, based on similar growing conditions / historical production regions:
1)
Melons are grown in semiarid areas in subtropical regions: Northwestern China, Greater Middle East (Turkey, Egypt, Iran, Algeria, Morocco), Central Asia (Kazakhstan, Uzbekistan), and the US / Mexico border region (northern Mexico, California), India-Pakistan region (northeastern India); historically watermelons were first used to carry water across desertic areas. Nowadays they're also grown in more humid regions (like Florida and the Southeast of the US, and Eastern China (around Shanghai), but I think this is a more modern development).
2)
Citrus would be a great addition in places with subtropical and Mediterranean climates: Southern US (California, Florida), the whole Mediterranean basin (not just Spain!), South America (Peru, Brazil), South Africa, Australia, and Eastern India, Southeast Asia (from Indonesia to southern China).
3)
Apples (and stone fruits) are grown in similar places: temperate, semihumid regions: western and southern Europe (from France to the Balkans), Turkey, Northern Iran, Russia (European part), Northeastern and Eastern China, Northeastern US, northern Argentina and Chile (and Southern Brazil). In general, stone fruits are more common in warmer/drier regions while pomme fruits are more common in cooler/more humid regions, but I wouldn't make any difference between them.
4)
Mangos, Papayas, and Pineapples are all produced in tropical, humid climates. They are different in that they were domesticated in different regions of the world and previous to the Colombian exchange Papaya, Guava (;esoamerica) and Pineapples (Brazil) were only grown in the Americas, while Mangos (Southeast asia) were restricted to the old world. Nowadays I don't think there's that much of a geographical difference. I'd put them all in the same category though, perhaps mangos can be the best representative for all? In any case, they're grown in places such as India, all of Southeast Asia (Indonesia, Thailand, Philippines), southern China, Mesoamerica, Brazil, Peru, Colombia, the Caribbean, most of tropical Africa (Mali, Nigeria, Kenya, Congo, Tanzania, Malawi).
5)
Dates and/or Figs, which are traditionally grown in very dry areas (especially figs), and serve as as important food source there (ie, drier places than melons), especially in the Middle East, North Africa, and Sahel regions (even in places like Saudi Arabia, and all the way to Sudan, Chad, Niger, and Mauritania). Less important countries are all outside this region and would include dry but agriculturally strong areas in China, the US, Mexico, Spain, Brazil, India.
- Grapes, keep them as they are, they mostly used for wine production, so I wouldn't put them in the fruit category at all.
- Berries overlap a lot with Apples and Stone fruits, the main difference is that they're also grown in highland areas in semitropical countries (like Mexico, Peru, and Eastern Africa); I wouldn't include them separately though
- I think that avocados, persimmons, and kiwi fruits are too specific to add on their own, and too difficult to group together with other fruits; also they don't cover different geographic ranges, so I don't see much point in adding them.
About bananas, though, there's something else to keep in mind. While they're biologically super close, bananas and plantains function very differently for people. Plantains are starchy and serve as a source of complex carbohydrates - they cover the same function as grains or potatoes, they're a staple. Bananas are sweet and serve as any of the other fruits above. Globally, bananas represent about 70% of production, and plantains the remainder 30%. However, the bananas only became massive in the 20th century, while plantains have been historically important as a staple in many tropical countries (where grains (exc maize) and potatoes don't grow well). Since I think most banana resources on the map are there to provide food in these tropical regions, I think we should consider the resource either the same as the other grains or at least as a different thing from the generic fruits mentioned above (just like grapes work differently because they're there for wine).
One thing to consider though about whether variants add additional bonuses or not, is that for some things having additional resources does bring more benefits IRL, and for some others, it doesn't. With spices, for example, there's a good argument that people get additional benefits from each type they get. I mention spices because it's one thing where it would be easy to think that pepper, cinnamon, and cloves could all only be graphical variants. Maybe variants can provide additional happiness, but not additional health?
Just some thoughts.