Hopefully, I don’t think that you are seriously advocating that we abort babies to send them to heaven. Maybe, you think abortion is moral for a more secular reason. And maybe you are using the assumptions of believers to arrive at an outrageous conclusion … just to have us on … to use an Irish expression.
But regardless your argument is thought provoking in this sense … it raises the theological question: why did God not just create angels? According to traditional Catholic theology, angels, not being in time and space, not being-in-the-world, instantaneously decide for God or not and immediately go to heaven or hell. So why did God create human beings who usually have to spend some time on earth before going on to the next life? Something to ponder. Heidegger asked a related question of Hegel: why did the Geist fall into time?