I hope you agree with my picks I tried to make this very unique!
Well, a couple things.
The Galapagos penguin AFAIK isn't kept in captivity anywhere, and is morphologically very similar to the African penguin we already have (not to mention we already have two penguin species representing both captive extremes), so it's unlikely it would be added.
The Sri Lankan elephant likewise doesn't differ hugely from the Indian subspecies. If we want more elephants, I'd rather they just changed the Indian elephant to a broader "Asian elephant" to make it more versatile.
The California sea lion is by no means endangered, and neither is the red-faced spider monkey (not sure where you got the name black spider monkey - I'm assuming you're talking about
Ateles panescus).
Hector's dolphin will never be kept in captivity again. New Zealand is extremely protective of its native species.
All in all, on that list I think the Amur leopard is the only species with a chance of making it into the game. For the exhibit animals it's more questionable. Kleinmann's tortoise (aka the Egyptian tortoise) is a pretty good fit, but it does depend on whether Frontier wants to keep tortoises as habitat animals. The axolotl, too, is a good fit, but as a fully aquatic amphibian it might not make it due to its unique nature (though, it could easily slot into the same exhibit biome as the diamondback terrapin, but whether Frontier would agree with me or not is another story).
IMO the best "Endangered Species Pack" would be a 7+1 animal pack.
I'd go with the following:
- Amur leopard.
- Tasmanian devil.
- Addax OR scimitar-horned oryx.
- Pere David's deer.
- Mexican spider monkey.
- Sumatran rhinoceros (probably the most unlikely of the bunch).
- Somali wild donkey OR Przewalski's horse.
- Mexican alligator lizard (for the exhibit; a truly beautiful lizard and endangered).
Probably too many hoofed mammals but I have a bias there (I don't think we have nearly enough yet).