The Qur'an would be a lot shorter if Muhammad and God had agreed not to repeat the same themes, the same stories, the same phrases over and over. But there is a reason for all the repetition: the Qur'an is poetry. In Muhammad's day, men who could compose good poetry and deliver compelling recitations were the rock stars of the culture. Lucky for Muhammad he had an excellent voice, and even luckier, he found a way to make beautiful poetry out of God's non-stop wailing over our failure to adequately stroke his ego.
I said earlier that the primary message of the Qur'an is that Muhammad is God's homie. But that's only the earthly part of the message, the part that applies to Muhammad. The heavenly part is that God, the infinite Yahweh, is infinitely fragile. God had to send Muhammad because Abraham, Moses, and all the other prophets could not entirely convey God's distress over the pagan Arabs worshiping other gods. And it was never good enough that even before Muhammad, the pagans readily acknowledged God's supremacy. They actually tried to work with God when he complained about their idol worship, which he referred to as "ascribing partners" to him. One of their prayers went along these lines: God, you don't have any partners, and if you did, they would be your slaves. Sadly, infinite vanity makes no allowance for such compromise. If you worship other gods, even if you also worship Yahweh, you'll go to hell.
It's not only the pagans who are in trouble. Christians are also doomed. Although I've never studied heavenly genetics, it's my understanding that being a son of God makes Jesus a god himself. But the universe just isn't big enough for more than one god. The early Christians worried a lot about celestial biology and its troublesome implications concerning Jesus. They attempted to solve the problem by inventing the doctrine of the Trinity, which makes Jesus a member of a mysterious hive-mind that functions as a single god. Muhammad rejects this notion vehemently. If you worship Jesus, even if you also worship Yahweh, you'll go to hell.
In his frequent exhortations to us to treat each other well, Muhammad seems to suggest that God can think of something beyond his insecurities. But this is an illusion. Consider: what should be the driving force behind acts of good will between humans? There's only one that makes any sense: compassion, a concern for suffering. Does God agree? No, compassion is irrelevant. For Muhammad, our fundamental motivation for everything we do, is the reward of heaven (or the punishment of hell). Even our attempts at compassion are tainted by God's vanity. Muhammad says when we do something good for the needy, we must tell them our charity is about God, and has nothing to do with them. God didn't create us to be compassionate to each other; he says so, in Sura 51 verse 56: "I created humankind only that they might worship me."
Without compassion as a foundation, virtue is entirely arbitrary. Underpinned by God's narcissism, it turns grotesque. Muhammad says we can get into heaven by dying--or killing--for the cause of Islam. And to be clear, we're talking about killing non-believers. Murdering a Muslim is a guaranteed ticket to hell. Why would God care if you kill someone who doesn't spend all day fawning over him? The bottom line in God's self-serving moral framework is this: no matter how compassionate you are, no matter how much good you do in the world, if you don't worship Yahweh, you'll go to hell.
The Qur'an is said to be exceptionally beautiful poetry. Perhaps this is true, if you don't know the language, if all you hear is a lyrical chant of unknown syllables. But in any language you understand, it's really just the story of God's embarrassing lack of self-esteem.