That's a crazy amount!
1. Two toed sloth (half a vote, the sloth would work perfectly as a walkthrough exhibit animal as well)
2. Pacific Walrus
3. Mantled Guereza (common monkey in zoos)
4. West Indian Manatee (one of the most ethical sea animals in zoos)
5. Tasmanian Devil (long time fandom's choice)
6. African Porcuipine
7. Squirrel Monkey (common monkey in zoos)
8. Tamandua
9. DeBrazza Monkey
10. Giant Eland (or common)
11. Markhor
12. Musk Ox
13. Conquerells Sifaka
14. Wolverine
15. Japanese/Chinese Giant salamander (most likely the only one possible habitat amphibian rep)
16. Alligator Snapping Turtle (habitat freshwater turtle, these can get really big)
17. Marabou Stork (these could easily be kept without any aviary, just like flamingo)
18. Tree Kangaroo
19. Gelada
20. Pelican (these could easily be kept without any aviary, just like flamingo)
21. Howler Monkey
22. Golden Lion Tamarin (common monkey in zoos)
23. Rockhopper Penguin
24. Green Sea Turtle
25. Secretary Bird (these could easily be kept without any aviary, just like flamingo)
26. Patagonian Mara
27. Serval
28. European Genet
29. Coconut Crab (most likely the only one possible habitat invertebrate rep)
30. Mata Mata Turtle (habitat freshwater turtle, these can get really big)
31. Nilgau
32. Honey Badger
33. Dromedary Camel
34. Andean Bear
35. Coati
36. Common Patas Monkey (common monkey in zoos)
37. Gerenuk
38. Grey Crowned Crane (these could easily be kept without any aviary, just like flamingo)
39.Black Rhino
40.Golden Takin
41.Aoudad
42. Vicuna
43. Adelie Penguin
44. Sulawesi Bear Cuscus
45. Numbat
46. Brown Kiwi
47. Fossa
48. Saiga
49. Red River Hog
50. Greater Rhea