I think that their needs to be more passive wildlife to make it a realistic feeling world I guess. I mean you can't have all the animals as predators right?
Also I think there should be more types of fish or sea life apart from the annoying slaughterfish
. You could bring back the Dreughs from Morrowind but I guess that wouldn't fit if it is a snowy type place. I remember I used a mod on morrowind which had a heap of passive sea life such as a lot of different types of fish (both passive and hostile), crabs, etc. Was awesome