Viability of an alternative method for Lakota and Haudenosaunee to collect gold.

Before anything this is not a thread to polemicize about the decision to change the way Lakota and Haudenosaunee collect gold, but to try to figure a gameplay trully unique and (I hope) balanced way to do this.

OK, we know that the idea to add the "Tribal marketplace" (it is the definitive name?) was to not make this civs mine the metal deposits directly, when historicaly the closer to gain money/gold/coin was through commerce. But in fact the game is still making Lakota and Haudenosaunee to mine gold just from a building, so what is the point? There should be a more interesting and historical way to do this.

Then we have the Fur Trade, we know this was a big thing for both natives and europeans, and the game already have many animals on the maps, then what about:

1- Lakotas and Haudenosaunee collect both food plus half the ammount of gold from animals.

2- The "Tribal Market" could be build close to wild animals and they would start to reproduce on some time (do you remember Empire Earth 1, on that game animals reproduced by themselves). This representing the management of the land.

3- Add some cards that send you animals named after some of the most notorious historical areas of huntting.

4- Under this mechanic the value of wild animals and metal deposits would be strategically different for Lakota-Haudenosaunee and the rest of the civs, adding another layer of interaction with allies and foes (like it was in real).

What do you think about this on gameplay terms, could be viable?

Feel free to suggest some values and rates to make it possible.