Turn wolves into something that won't immediately kill you the minute they show up on your minimap. OR, make a variety of wolf, like 'Lone wolf', that is not immediately aggressive. Let us give wolves clover, leash them, beat them in pens, and tame them. They could turn into a random breed of dog when tamed, like how mouflon turn into sheep. You can leash these dogs and bring them to places, then unleash to perform different tasks. Interacting with them while they are not leashed will give you the option to have them follow you - and if the engine allows it, they will even follow and board rowboats, snekkjas, and knarrs. If they are not leashed though, they will try to perform their action even while following you. The dogs are auto-branded when tamed, and only the owner of the animal can give directions to it. They are able to keep up with horses, so they have no problem following on horseback.
Hound dogs (beagles, basset hounds, and foxhounds etc) : when unleashed will chase and kill small animals nearby. This includes birds, rabbits, squirrels, stoats, moles, adders, hedgehogs etc. Bonus points for bringing them back. They will not attempt to fight bears, boars, mammoths, or other large animals.
Working dogs (Boxer, Great Dane, Rottweiler etc) : When unleashed, they will attack any player who is not kinned to the owner of the animal.
This would be useful for self-protection, by keeping working dogs near the entrance of your claim they could make raiding mid-game significantly harder, and could also be used to wreak havoc on other people's claims during raids making raiding significantly funnier. I would not imagine these dogs should be very difficult to kill, just for balance sake. Something like a little weaker than a boar. Just enough to be an inconvenience.
Herding dogs (Border Collie, German Shepherd Dog, Pembroke Welsh Corgi etc) : I'm running out of ideas. I think the sole purpose of these dogs will be to keep dangerous animals away. Every wild animal, except for adders and insects, will be repulsed the moment they see these dogs. They are great at defending livestock, and make great companion animals for travelling with via wagon or horse, just to make life a little easier.
Toy dogs (Chihuahua, Pug, Shih Tzu etc) : You fucked up. In haven and hearth fashion, these dogs exist to make taming harder. They don't really do anything special except walk around and look nice. maybe make it so they can be picked up and stored in your inventory (3x3 space?), collected, traded, etc. These dogs will take orders from anyone, meaning they're easily stolen. Not advocating dog violence, but would be kind of cool to see them drop special hides that could be turned into capes or shoes.
They normally act like any other animal when leashed up, except that you cannot breed them. This is to avoid mass breeding for working dogs, but if there's a script for taming dogs that would still kind of suck.
They will eat anything from a trough like every other animal.