I read from an Orthodox priest (don't remember which one) that remission was greater and more complete than forgiveness.
When it comes to the Protestant idea of imputed righteousness, where people are not made righteous but just seen that way by God, I suppose it would make sense for a Protestant to want to get rid of remission (as the greater, more complete).
Father Matthew the Poor said that, when Christ was crucified, water and blood flowed from his side--water to wash away sin, and blood to withhold its power. In my estimation, the water signifies baptism, and the blood the eucharist. And, in terms of this sort of discussion, water for forgiveness and blood for remission--although this isn't exact because we say both baptism and communion are for remission of sins--baptism for remission of sins in the creed, and communion unto remission of sins and eternal life in the Liturgy.