Dogs. Cats can be temperamental and too dependant.
Raising dogs from pups is an unbelievable experience. When I was 5 my father bred and raised a litter of 5 hunting hounds, beagle x foxhound, just recently the last of the litter, Patch (Very original) died.
Although sad, looking back on the life of the litter it was amazing. Dogs, especially working dogs are so eager to please, whether that be in their role while hunting or general frolicking in the fields.
For an animal that was bred for fixed assets, it's nose and prey drive, their loyal and obliging temperament made them great family pets also.
I've never truly had a "Pet", as in an animal that serves no purpose other than companionship but the satisfaction of raising and training a pup from birth and seeing it carry out it's given task (Cover hunting, coursing, killing or retrieving, etc.) is immense.
Some may see hunting using running dogs, sighthounds or grounddogs as a tool for hunting cruel but only those who understand working dogs would understand their prey drive, eagerness to please and need to be given a job or task to carry out. Collies are a great example of this, non working collies become agitated or even viscous. From my experience, aren't the overwhelming majority of the "tailgate attackers", collies? Non working collies must be given intense obedience training and many are kept busy with agility training.
What was the question again?
TL:DR - Dogs.