Varying amounts of grace and peace?
D. Whitehead comments on 2 Pet 1.2:
It seems that the amount of grace and peace that floods our heart is directly related to the knowledge of God and specifically of Jesus Christ. Our minds don’t naturally gravitate toward grace and peace—we keep trying to prove ourselves, resulting in stress and condemnation. But the person who focuses on the Scripture everyday opens a portal of provision to their soul. The knowledge of God captures our wandering thoughts and the results are delightful.
At first thought, it seems strange to think of varying amounts of grace and peace in the heart. But if faith can grow, why not these? Their relation to the knowledge of God and of Christ is direct. So the first phrase is quite right.