I like your ideas. I've been thinking about pack ideas for a long time as well. Some i agree with you.
I don't think that is likely to get another asian building set (even if we it would be cool to have for SEA), but instead i see an animal pack as something more likely. As for central america i would like for it to be two 4+1 pack with building sets, one for the caribbean and one for mexico (yeah i know is technically part of north america but it would make for a great dlc full of props).
Somethin it don't think will get but i would like is an indian animal pack.
And i can deffinetly see the middle eastern and the african/oceania animal packs.
That said my wishlist is similar to yours:
SA animal pack (7+1)
1. Capybara
2. Maned wolf
3. Greater rhea
4. Black or red howler monkey
5. Sloth
6. Ocelot (if we get it in a mexican or central america pack then maybe the brazilian tapir or spectacled bear)
7. Black/spectacled caiman
8. Emerald tree boa/green anaconda
Carebbean pack (4+1)
1. Caribbean flamingo/caribbean brown pelican/scarlet ibis (one of the three, i don't think we'll get more than one bird if any)
2. West indian manatee
3. Green sea turtle
4. Squirrel monkey
5. Lesser antillian iguana
Mexico pack (4+1)
1. Collared peccary
2. Ocelot (if we get it in the SA pack then the nine banded armadillo)
3. Mexican spider monkey
4. Cacomistle or coati
5. Axolotl
Middle eastern pack (4+1)
1. Arabian oryx
2. Dromedary camel
3. Caracal
4. Hammadryas baboon
5. Uromastyx
I can see this pack being an animal pack as well since we got middle eastern architecture with the Africa pack. If so the other 3 animals i can see in a pack like this are arabian leopard (if we don't get a leopar in the africa animal pack), striped hyena and possibly the nubian ibex.
African animal pack (7+1)...
A lot of overlooked, popular and needed animals in this one. The game somehow would feel totally incomplete if most of these are missing by the end of dev support.
1. Black rhinoceros
2. Nile crocodile
3. Secretary bird
4. Grey crowned crane
5. Black and white colobus monkey
6. Greater kudu (or red river hog)
7. African leopard
8. Black/green mamba/gaboon viper
Madagascar pack (4+1)
1. Fossa
2. Indri
3. Sifaka
4. Tenrec
5. Panther chameleon
East asia animal pack (7+1)
1. Przewalsky horse
2. Amur leopard
3. Sichuan/golden takin
4. Golden snub nosed monkey
5. Sarus/damoiselle crane
6. Golden pheasant
7. Mandarin duck
8. Japanese giant salamander/fire bellied newt
Indian animal pack (7+1)
1. Indian leopard
2. Ratel or striped hyena
3. Blackbuck
4. Gaur
5. Lion tailed macaque/hanuman langur
6. Chital deer
7. Sloth bear
8. Indian cobra
Oceania animal pack (7+1)
1. Emu
2. Platypus
3. Matchie's tree kangaroo
4. Wallaby (any kind)
5. Tasmanian devil
6. Kiwi
7. Wombat
8. Tuatara
Endangered animals pack
1. Gibbon
2. Sumatran rhino
3. Saiga antelope (Amur leopard if not included in asia dlc)
4. Addax
5. Aye-aye
6. Black footed ferret
7. Chinese alligator
8. Lord Howe Island stick insect
Polar animals pack (7+1)
1. Wolverine
2. Musk ox
3. Rockhopper/emperor/gentoo penguin
4. Walrus
5. Atlantic puffin (or another species of penguin)
6. Sea otter
7. Harp/leopard/elephant seal
8. ?
As for the aviary pack i think it sholud be a true expansion pack since it would require new animal and building mechanics. As such just 8 animals won't cut it for me, specially considering how much Frontier has been neglecting birds in the animal packs (intentionally or not). So for this one i didn't fully followed the rules since i selected 15 species i think should be included in this kind of pack to fill all the types of birds we need
1. Scarlet or hyacinth macaw
2. Toco toucan
3. Indian hornbill
4. Harpy eagle
5. Bald eagle
6. Andean condor
7. Griffon vulture
8. Scarlet ibis
9. Roseatte spoonbill
10. African grey parrot
11. Snowy owl
12. Great horned owl
13. Reggiana bird of paradise
14. Victoria crowned pigeon
15. Large flying fox
Even with 15 animals we get short ( i would love quetzal, hoatzin, phillipne eagle and turacos but they are not high priority unfortunally), but a lot of "not-aviary" birds should be included in the other packs to compensate this such as galliforms, ducks, geese, swans, cranes, storks, pelicans... and later on the flying mechanic implemented on them in future updates.
As for exhibits maybe small aviaries for small birds such as passerines or even for small bats like the honduran white bat.
In conclusion... so many animals we are still missing and so much potential for countless dlcs. These are the ones i thought about. Sorry for the long post.