Is there such a thing as the perfect puppy? In all likelihood there is not. There is always something one might change in any dog (or person really), but the goal should be to always strive towards raising a puppy to be its most perfect self. This is hard work, to be sure, but it is not only possible, it is necessary.
The personality of a dog is flexible and indeterminate. Dogs can be exuberant or shy; friendly or hostile; fearful or bold; aggressive or passive or some combination of the above. These differences in personality may to some extent be determined by breed, or individual genetics, but for the most part it is based on how and to what extent each particular dog has been socialized.
A well trained SAR dog is a sight to behold. The dog can evenly maneuver the most difficult of terrain with the grace of a mountain goat all the while looking for a trapped or hidden human being. This type of work is often done on the fly, at the drop of the hat, with little advanced warning. It requires a talented dog and a special handler willing to invest the time and effort.