I think this change to the world map is quite possible and "easy" to implement.
It involves creating another world map tab, but one that only shows small reserves, while the existing tab would only show normal or large reserves. It would be exactly the same as the one we already have in the game, but it would only show the small reserves, and the normal or large reserves would be shown in the one that already exists in the game.
This change would affect the creation of future large reserves, since it would only be necessary to have one or at most two small game species in the reserves. It would also increase the number of big game species in the reserves, since there would be more small reserves dedicated to small game that would accommodate the small game species.
I developed this whole concept to avoid having a glutted world map, since in the future more reserves, both large and small, would be created, and by having them separated, there wouldn't be a single glutted world map. Although I thought about this whole idea because I would like to see more small game reserves in Dakota, New Zealand, Spain, Argentina, Canada, Alaska, etc.
This idea could be applied in some way to the reserve selection in the main menu to make it easier to choose the type and size of the reserve you want to play at any given time.
All of this is an idea/concept, it can always be improved, changed, etc, or even discarded.