Well my dos centavos:
1: Lucifer / evil concept allows for a redeemer and does away with the dichotomy of God being omnipotent and benevolent yet allows evil.
2. the concept of Satan is a ancient Babylonian myth
3. The Garden of Eden story also allows for the down fall of man into original sin, thus re-enforces how Satan can be responsible for corrupting humanity.
4. Biblical text refers to God as the quiet calm after the storm, not the storm itself.
Is God evil? I would say no. The bible has implimented a background of carefully selected stories, but depending on which Judeo Christian God you are refering to, Fire Wrath and Brimstone, Or Kind and good. He is that he is.