Interesting thread.
I believe making a 10-animal only DLC is way too much, unless Frontier suddenly decides to shift to an expansion pack system like in the old Zoo Tycoon games. If they stick to the current way, I can see them adding two Africa-based small DLCs in the long term, each one with its own animals, facilities and building sets.
AFRICA PART 1
Animals
- White or Black Rhinoceros.
I can see Black Rhino probably getting added to Planet Zoo in virtue of its critically endangered status. For gameplay purposes, I'd like to see the White as it's a more social species.
- Meerkat
It's one of the most popular animals they left out in the original roster. It's a staple of most zoos and instantly recognizable. It could be the draw for people to get this DLC in first place. It also could come with new enrichment items like a lookout post or underground shelters.
- Secretary Bird
Mainly because of Zoo Tycoon 2 nostalgia, but also because its a ground-dwelling, large and conspicuous bird of prey. In a game where the current mechanics don't allow for small or high-flying birds, the Secretary Bird could be a small treat for bird enthusiasts (the Shoebill could also fill this slot)
- Hamadryas Baboon
I chose this instead of the Olive Baboon for the sake of biome diversity. It could also tie with the Egyptian building set.
- Black Mamba or Ball Python (Exhibit)
There are a lot of well-known snake species in Africa, yet the only one in the original game IIRC is the puff adder. Why not some more variety? The mamba could be an interesting one because of its reputation. The ball python is one of the most common reptiles in captivity and as such it could come in many color variants.
- Ancient Egyptian Building Set
Besides being suitable for desert themed areas, the abundance of animal motifs in Ancient Egyptian lore could be specially great for statues (gods, etc.) and other scenery items.
AFRICA PART 2
This would be a smaller pack centred on animals and building sets additions.
- Serval.
It's one of the most frequently asked small carnivorans for the game, and would help to tackle the lack of small cats in the original roster.
- Fennec Fox
A charismatic small desert canid that is widespread in captivity and so cute the developers wouldn't miss the chance of marketing a DLC with this critter in the spotlight.
- Greater Kudu
Kudus are one of the most iconic antelopes, thanks to the impressive look of the spiral-horned males. The only downside is that it would be too many antelopes of the same genus (after the Bongo and Nyala). To priorize diversity, maybe the Gerenuk or Addax could take its place.
- Guereza
Adding a rainforest-dwelling arboreal monkey for a change of pace from terrestrial ones like Mandrill and (hypotethically) baboons. Besides, colobus monkeys just have a striking appearance.
- Panther Chameleon (Exhibit)
Chameleons are missed in the original roster, so adding the colorful Panther one to boost the lizard diversity and having at least one creature for Madagascar (speaking of which, I seriously considered the Fossa in one of these slots, but I think it could be better served for an Island-themed DLC).
- Expanded African Building Set
They could add new blueprints based on Zulu or Masai villages, or some jungle-based scenery and building items like Great Zimbabwe ruins.