It does not seem proper to speak of one attribute of God as being more central and fundamental than another; but if this were permissible...

I agree that we should not separate one attribute of God from another but can someone please explain to me why it is not permissible to speak of some attribute of God as more fundamental then another?

The Bible states that "God is Love" but would that be even possible if God was not Holy? Therefore, the fact that God is holy, gives foundation for God to be love. (Being holy gives him the ultimate authority, thus why did he need to die for us. Because there exists no reason of need -- only because he is holy -- the reason can only be because he did it out of love). Thus, I understand God's love in that He is holy; God's holiness is fundamental for His love.