Hmm... I don't quite agree about the dragons – these "Godzillas" – azure, crystal, rusty, and magical dragons – in my opinion, are overpowered and unfair. And if someone gets them as a result of diplomacy, that would be quite something!!! We don't need overpowered units; we already have neutral phoenixes... (which, by the way, could use a nerf). But normal dragons, ones that fit within the maximum unit limit, are fine – because you can come up with many ideas – a sea dragon, an ice dragon, a storm dragon – that's just the beginning...
Werewolves – I agree!!! And also Beholders (evil eyes), troglodytes (those blind lizard creatures), poisonous creatures (from the 4th game), ice demons (also from there), nomads, wolf riders, trolls, ogres, hives...

P.S. Ar – and what did you come up with to replace the black dragons, minotaurs for the Nihon faction, and hydras for the Swamp faction??? By the way, replace the gnolls too – they just won't get along with the lizard creatures.

Humans could have a griffin as their animal... or maybe replace it with an eagle.
Elves could have a deer, you can tell by the helmet... although I don't really like them.
Barbarians could have a steppe horse.
What about the mages? A camel? An elephant?

But I don't know what to give the demons... maybe lions with fiery manes or hyenas, fiery salamanders, although they look like snakes. No, that won't work.