How about not releasing any animals until the prices come down, instead of the same old 375 crystal bridges and safari hats? And not to mention until content has been released to everyone - including the
outback and
cross breeding - which already gives some players much more animals than others! As an Aussie myself, I would love the Koala, Platypus, Frilled Neck Lizard etc that are available with the Outback, but I, along with many others are yet to get it!!!
That said, some more region quest animals would be nice. I wished the Homestead, Safari, Dinosaur, etc. animals etc came with their own land and landmarks etc. As they didn't, I wouldn't mind seeing some more coin-decorations in the shop to reflect such regions that didn't come with their own landmarks, so we can create our own little coupling and space for them

Even the Haunted island animals, who were all crystal animals, did come with a little quest and landmark for them.
As for other animals, like Eleni said I wouldn't mind more aquatic animals, although not sure how you'd wrangle that... I think either way they're gonna look weird clearing things unless they were somehow underwater.
And definitely agree with Moosh - would love to see an Owl and an Eagle! Maybe even something more colourful like the Rainbow Lorikeet or the Toucan, or more beachy like the Pelican.
With Halloween coming up, maybe a Spider?