A good dog concept could be dogs like coon hounds or curs treeing animals like raccoons,bears,mountain lions and bobcats this could also add a new feature of animals climbing trees to get away from a hunter
Perks : for the dog like how the blood hound can track for a further distance a dog like a coonhound would be more likely to smell a bear hiding in a tree. And a multiplayer feature is if you have multiple people in a session and you all have hounds a perk that could be added could be a mobbing effect that something like a bear or mountain lion would stay in a tree for a longer period of time and would be more likely to run up a tree rather than staying in the ground and running away. Another perk that could be added could be a fearless perk that if an animal climbs down a tree something like a bob cat or raccoon there could be a chance that the dog would growl or nip the animal to get it to go back up that same tree