Personally, I'm hoping for the opposite - the broader the better. Once North America and Europe/Eurasia get their turn I think it's best to move on to DLC covering broad, globe-spanning themes (whether related to biome or conservation status or whatever) that could include as many animals from around the world as possible, rather than doubling down on regional specificity.
I understand that way of thinking, but i just rather have some more fleshed out regions after we get finished with the "base raster" of the game, instead of just a bit here and there.
One of my main complains about the base game (and in someways also the dlcs) animal raster was, that it just was not a good base raster for a zoo game. Africa was great, even if there were only little exhibit animals, Asia was okay, we got most of the big hitters, but allmost none species that wernt "spotlight" animals. From the top of my head only the bactrian camel, red panda, peacock, pangolin and maybe the japanese macaque come to mind as animals, that would be "just another exhibit" and not a 5 star popular animal, and even here im stretching. Luckily the SEA dlc mostly fixed that problem. America had just pitifull 4 habitat animals, europe had 2, south america 2, but a good amount of exhibits and australia none.
Then the first dlc came and whatever your opinion is on the animals, they nicely supplemented the American raster (and european raster lol) and gave us both a big star animal and 2-3 more general animals, that you would see in the zoo but wouldnt lose your about.
Same thing for southamerica, but here notably it was a bit worse, as the base game raster had only 2 more animals and just now after the aquatic pack was boosted up to an atleast okay number. Australia had even less to work with, making it one of the best dlcs animal wise, but at the same time being severly limited by the lack of anything else besides 2 exhibits in the basegame. Aquatic started fixing the problem and patching up the holes in both the arctic and south america dlc and SEA patched up the missing asian filler creatures.
When the NA and Europe pack will come around, depending on how the animal picks there will be atleast 9 european and 13 northamerican animals in the game.
At that point the only continent in dire need for more would be oceania and the basegame problems of the raster would mostly be "fixed".
As we wont "need" anything anymore at this point to make the game fill complete the dlcs could literally be what ever and i hope they will keep adding more "filler" animals to supplement what we allready have in regional packs to represent the local fauna of a specific region (and i really mean region, no continents anymore but choosing some ecosystems to fill out, the best would obviously be some that are allready some what represented in the basegame, for example we have the apex predators of the Himalaya but no prey species or even herbivores besides the red panda) instead of just some big packs with allstar animals.
But thats just my opinion and everyone their own, we just have to see what frontier will actually do once they are finished filling in the obvious blanks