Well obviously we need building pieces, plus four birds which could become base for future animations; parrots, birds of prey, waterfowl, and big beaks.
Considering that I'm thinking:
Blue and Gold Macaw
Toco Toucan
Bald Eagle
Scarlet Ibis
But if more possible I'd add at least three more:
Great Hornbill
Snowy Owl
Victorian Crowned Pigeon (base for future pigeon likes )
Hope this helps
PS: sorry I've only noticed after reading again lol! I'd say Californian Condor cuz it's endangered species, reference to San Diego Zoo, also provides large base skeleton for animating future raptors