Varies. The "perfect" contraceptive for any particular woman is the one that is simple, easy, and available and that provides excellent contraception with minimal side effects, inconvenience, and expense. It will not necessarily be the same for every woman.
Many options. Majority of contraceptive options for women are highly effective if used the right way. The "perfect" one would be something that would be affordable and practical for you. It should be one that you would be most compliant with taking or monitoring and at the same time give you the least amount of side effects. There are many options for you to discuss with your doctor.