What about every civ having its own animal unit?

You can use wolves in the campaign, what if every civ had a trainable unit like that? based on region they could have tigers, lions or bears. Probably not a lot of historical accuracy but could be fun. I was thinking maybe trainable at the town center. Could function as a slightly faster but weaker version of the militia. Slower than a scout with less HP and no armour in addition to a gold cost to balance roles. What do you think?