The Church's view is not based on ending a "potential life", unless you are referring to the "backup" mechanism of an OCP whereby if conception does occur, the body rejects it. However, in this case, the pill is not working as a contraceptive but as an abortifacient (keeping in mind, of course, that the Church believes life begins at conception). The Church's opposition to contraception deals with the meaning of sexuality. As you noted, the purpose of sex is both procreative and unitive, binding the couple closer together in a spiritual union which is manifested in a physical union - a new human being. The Church's teaching about contraception is essentially the same as it's views on homosexuality and masturbation, all of which deny the truth about sex.
Your view sounds rather marxist, as though human fulfillment is synonomous with economic stability. The Church's mission in the world is not to eradicate poverty, but to manifest God's love for mankind. Granted. one way of doing this is by serving the poor, but not with false solutions. Since the introduction of OCPs into the mainstream (which is a recent historical phenomenon), the incidence of STDs and unwanted pregancies has only increased.