The idea of cursing others in prayer is anathema to an orthodox Christian. After all, it breaks all moral precepts. It seems wrong to ask God to take vengeance against those who’ve betrayed and wounded us. Besides, we shouldn’t even think such things—Jesus clearly told us to pray for our enemies, not curse them
Thank you for tackling this very difficult part of the Psalms. Many do avoid it because it doesn't seem in keeping with the usual ideas we have about Christianity. But based on my experience, it is the difficult verses that help us understand God more (and ourselves, too!). They help us to pray for guidance because it is so hard to deal with it by ourselves. These verses also serve a purpose, a very deep one. In a way, I think it was left there to help us know that God understands our humanity and our frailties. Wasn't Jesus Himself the one who asked, "My God, why have You forsaken me?"