My opinion is that the best thing is not to have extra pets !
I think that if you are only acquiring a pet to have as a pet (as opposed to raising them), then having the pet neutered is the best thing to do. That way, your pet will not reproduce, nor wander off looking for a mate if it is a male.
This is one of the biggest reasonss that we have so many unwanted pets, is that people do not properly neuter animals that are not intended for use as breeding animals, and then they have to decide how to find homes for the unwanted and sometimes unexpected offspring.
The new owners often just continue the cycle with the puppies/kittens by allowing those to grow up and also reproduce; and eventually, there are simply way too many pets for the available homes for them.
People who are raising pedigreed puppies/kittens/rabbits, etc. to sell, usually know that they will have a market for the babies when they arrive, so those animals will mostly have a good home and be taken care of, since the purchaser had to pay to acquire the pet.
This is not always true, but it seems like people who spend money buying a pet will also spend money to properly care for the pet and make sure it does not randomly produce unwanted babies.
