The game's setting would make some of these animals a bit awkward to implement, i mean, H&H is basically Northern European/Germanic (think gauls) in its lore, shouldnt we have animals native to that region?
In that vein, i would like to see the rats, toads and chickens have a use, as they have none other than just being part of the background......Perhaps we could have rats as pests that can eat food found in a civilized area, maybe spread some disease? Im not sure about toads, chickens though can make for a supply of feathers, meat and eggs, maybe the feathers can be used with arrows to give them flights, which adds a to-hit multiplyer to them, allowing better chances to hit.