Absolutely, one should pray for the lost, as that is within Gods will, that all should be saved.
Often I pray that God will bring believers into the lives of my unbelieving friends and relatives.
And your prayer for others doesn’t mean that you believe that Jesus’ sacrifice was not enough to get “all the way there,” correct?
So, to sum up, when you pray for people that you think need God’s mercy, it is not a denial of Jesus’ sacrificial sufficiency, but when Catholics pray for people that we think need God’s mercy, it somehow is a denial of the sufficiency of Jesus.
Interesting.