I found this on about page 10 and just thought it brought up some good points no matter what breed you are into:

The Ten Commandments of Breeding
By Shiela Varian (as in, from varianarabians.com)

Yes this is about Arabians, but I'm sure you can be creative and apply it to your own breed.

by Sheila Varian

1. Breed toward your ideal horse. Dont be swayed by the voices of others. If you have done your homework, in time others will appreciate what you have accomplished.

2. Recognize that you are breeding Arabians and stay within your interpretation of the breed standards.

3. Breed equally for Arabian type, performance qualities, disposition and trainability.

4. Never forget: No foot, no horse.

5. Always strive toward a horse of usable disposition, plus beauty. Neither is good without the other. However, if forced to make a choice, Id keep the usuable disposition.

6. Follow the lead your horses set for you. The next generation need not be similar in phenotype to the generation before, but each generation must be consistent in overall quality.

7. Breed forward. Look ahead. Wonderful new surprises may be awaiting you. Recognize them when they occur.

8. It is not difficult to improve the produce of a poor quality mare in one generation. It is not even difficult to improve the produce of an average mare in one generation. What is difficult is to improve the produce of an exceptional mare generation after generation. That takes real skill, knowledge, gut instinct, and vision.

9. Dont be afraid to appreciate the qualities of others horses. Breeding is a competition with yourself, not with others.

10. Consider your horses attributes before you consider his/her negatives. All horses have both. It is for you to determine how positive his/her good qualities are before you dwell on the negatives.