Here is a example of taking two breeds of working dogs and reinforcing some of their strongest traits. (Of course, a couple of the less desirable traits may possibly occasionally rarely infrequently from time to time, every now and then, once in a while, make an appearance).
The Bloodhound is known world wide as one of the greatest trackers of all time. Their nose knows of no other nostrils nearing their normal natural ability to track the scent that their snouts smeller sniffs. Without guidance they sometimes try to follow more than one scent at once. Don't bother to try to give the Bloodhound orders. They have a mind of their own, and pretty much do as they want, which is to smell, track and smell some more. (They also have a tendency to howl, snore and drool a bit. Okay, a lot).
The Labradors are known as exceptional gun dogs. (No, they don't carry your guns, but I suppose you could strap one on).
Ideal in temperament, they posses an outgoing, tractable disposition, making an ideal pet for a family, and are often used as companion and assistance dogs. A side benefit is their ability to function as a garbage disposal, although the bypassing of natural gasses are problematic to some.