I read a tome on Satan a few years ago. )People tell me that Jews view Satan as a powerful advocate for humans. He asks God moral questions. If one goes with what 99% of self described Christians believe, there is little to fear. Satan is created and, therefore, no problem for God. I think we read a lot of different strands of thought concerning Satan in the Bible.
Other religions believe in demonic possession. Unlike the Witnesses, though, they are repeatedly told to have no fear because God gave them the power to rebuke demons in Jesus' name. So much of the WT view reads as though God and Satan are equal contenders. Jesus could get no lower in power. Witnesses are the only true Christians yet we do not bear Christ's name but Jehovahs.
I believe the book is called Satan and runs about 1,000 pages. The basic theme if how pictorial depictions of Satan change as society undergoes change. There were few depictions in early Christian art and the modern trend is markedly proSatan.
Satan transforms from Jewish thought to Christianity. There must be a reason.
C.S. Lewis, Screwtape Letters is my favorite book about Satan and demons.