Imo, fixing up NA and Europe can be easily dond with adding just 4-9 animals that fit well in more general packs.
For NA, the biggest sour spot is the south, making the collared peccary with its range also down to south america a great option, especally for a desert pack.
The next is the lack of any climbing or aboreal animals, where introducing the racoon would do wonders, especally as its one of the most common Zoo animals world wide.
After that, a bird like a Sandhill Crane or Turkey would be nice, but isnt as needed to make the continent feel on par with the others, as sadly none have enough birds.
For Europe, their are 2 Unarguable inclusions that still need to happen.
The Wild boar and Red Fox.
Both have gigantic ranges across all of Eurasia and the Red fox also in NA, both would compliment the existing members of their familys really well and they are also omni present in smaller Eurasian Zoos.
If they are in the game i would still like more europe, but would also be totally fine with no more.
A great addition thats also in the Top 10 of the meta wishlist is the Wolverine, pretty much completing europes skandinavia focus while also offering something for NA.
After those 6, their are 4 more animals that would greatly add to europe and the game, but arnt what i would count as completly neccessary, just really really nice to have.
First we got the red deer, it was often argued for it on the forums as its a bit mire controversial, but the baseline is that its very common in Eurasian Zoos, is culturally important, visually distinct, has very unique and impressive roars and would greatly differ from the petting zoo fallow deer we got (which is not a front, for a long time it was my most wanted animal and im glad its here).
A marten has basicly the same reasoning as the Racoon, but they are much more rare in zoo in comparison, still decently common on their own, but i would be okay with their exclusion if we get the racoon. Btw Team Beech Marten
A european bird would be great, from the generic mallard duck, over the mute swan, white stork and common pheasent to the western capercaillie, it would be amazing to have atleast one of them represented and imo the only fault of the european pack, no matter how much i like its animal roster, was to not include one of these birds. If they dropped the badger for a white stork or mute swan, i would have been estatic.
Lastly, another controversial one, the Eurasian otter.
Its the most wide spread otter, covering all if the biomes in game, being present on 3 continents and would add an all weather but mostly cold weather and solidary otter compared to ours in game, which are both tropical and social.
They also perfectly fit into the size gap between + their solidary nature would make the perfect for smaller habitats.
Also let me quickly show you something
(Server doesnt let me upload the picture right now, but it shows its massive range from the norway fijords, over the deserts of the middle east to the tropical rainforrests of sumatra)
So yeah, thats my take on the whole europe and na discussion, and atleast imo my points for which animals still should be included in for example a temperate animal pack.
But as it stands right now, NA and especally both europe arnt "finished" until their last gapping holes in representation (mostly birds, racoon, wild boar and red fox) are filled. Until those animals are in the game, i wouldnt say NA has great or that Europe even has good representation, in school grades current na has 12/15 points and europe 8/15.