It's better to have the odds working for you. Actually, breeding close is the only practical way to improve a line. The base stock, obviously, has to be superior quality. There is no precise answer. While one person will see much joy in raising a puppy, another may view the process as a series of hassles.
Puppies chew, whine and are more prone to illness.
Regardless, the training needs to start early. Don't expect a good started dog for a puppy price. It's far to expect a started dog to be well-conditioned, obedient to basic commands, birdy and show a desire to please most of the time. We like to think of our started dogs, in human terms, as ready for high school. Most of us respond to common decency with the same.