To an outsider, or to a lukewarm Catholic, sacramental confession is just an Incarnation of the Monopoly games 'get out of jail free' card. I suppose, in a sliver of this sacraments rich truth, this is correct. It is, after all, the meeting place of the Crucified and Risen Jesus, in all of His Abundant Mercy, where His Blood cleanses us of our sin, and sets us free from an eternity of hell, where we would be lost from the Love of God in a cocoon of our own making, freely chosen, in self-absorbed sinfulness.
But this would only be the tip of the iceberg.
First of all, forgiveness of sins does not free us from the temporal punishment of sin. Though Mercy triumphs, Justice remains. When we sin, we are saved through confession, but we must still 'pay the piper,' so to speak. Purgatory, or our perfection prior to entering the Life of God in the beatific vision (Heaven), is the painful, but joyous price of cleaning up before stepping into God's Perfect Love. But sacramental confession, properly understood, is an enormous source of grace for this very same purgation as we willingly submit to God's Will, purging ourselves of our sinful ways. Therefore, this sacrament is more than forgiveness, it is a powerful source of grace in a transformation from our old selves into our new selves in Christ.
Confession is also the ultimate source of humility.
Think about it. Reality is the safest place to be. Reality is our sinfulness, and God's Loving Mercy. Reality is our reliance on God. And, apart from the Eucharist, the sacrament of Reconciliation (confession) is the greatest reality, and reminder, of our relationship with God.
Confession is also Reconciliation.
When we sin, even venially, we turn from God. The God of the Cross, and the empty tomb, Loves us dearly. Confession is an 'I am sorry' to the One who truly loves us--in the Godhead of the Trinity, and in His Body, His Church. Confession is also reconciliation with ourselves. When we sin, we become less of the Image of God we were created to be. When we confess, we become more.
Finally, confession is to the Eucharist what dressing nice is to a date with the One we Love. Confession shows our Love, through God's Mercy, for our Lord and Groom. Confession says, 'I desire to receive you more than Life itself.'