Currently, the zoo keeps many types of species in them: birds (ibis, curassow, hornbill, crane, seriema, eagles), primates (lemurs, a wide range of monkeys, gibbons), small carnivores (ocelot, fossa, previously otter), and a couple of reptiles (tortoises, and also the Komodo dragons and perenties in the Australian realm). One also holds a giant anteater (mixed with saki monkeys, I think).
Of those species, I think the small to mid-sized primates, the reptiles, the small carnivores, and the less flight-oriented birds (like curassow and hornbill) are good species for those enclosures. For the raptors and tall birds, larger monkeys (like mandrills), gibbons, and anteater, I think they should probably have larger enclosures, but even then I don't think the current ones are inadequate (except for the raptors; sea eagles and condors should, IMO, have sizable aviaries dedicated to them).
Edit: I keep thinking the anteater should also have more space due to their size, but they also have really low metabolisms so it may be fine.