Very fair point - I admit that I'd not really realised that, most likely as a result of zoo theming (where's the facepalm emoji when you need it?

). I agree with you that, even if it requires more generic 'Americas' theming, if a crocodilian species is included within such a precinct, it most likely would be the American Alligator.
There's also a slither of space down the hill from the former croc exhibit, which is currently uninhabited jungle. While I'm occasionally hesitant to recommend building exhibits in areas of established canopies for fear of damaging the trees, this area of Taronga rivals Melbourne's rainforest areas in terms of established jungle, and is currently quite under-utilised.
Personally, I'd love for Taronga to reacquire tapir. Tapirs are some of my favourite animals and, considering that Malayans are on the way out, being involved with a rejuvenated program for Brazilians would be wonderful in my eyes. I agree that the new RAAC, especially if it takes up the space of the current gorilla exhibit as well, will separate the zoo (being a building) in a way that the current use of the land doesn't, so turning the area between that, the concert lawns/B2B, GSO and the bottom of the zoo into something exciting would be great.
One thought which I did have in regard to the Congo Forest precinct is that the initial construction boundaries seemed to extend right down to the path and right down to the corner opposite the food market, just above the existing gorilla exhibit. This area now contains a toilet block (on the map called the SC Johnson Family Room) which I believe was built during the African Savannah construction. While I'm not saying that the zoo is hampered in progress by where a toilet block is located, I do feel like the zoo is potentially unlikely to demolish such a recent construction, so this could indicate that the toilet block will remain on the outskirts of the Congo Forest (or, I could be completely wrong, and they could just knock it over as soon as they catch sight of an okapi

)