Reddit mentions of Logic, Rhetoric and Legal Reasoning in the Qur'an: God's Arguments (Routledge Studies in the Qur'an)

I wouldn't say that the point is obedience. The Quran commands virtue, fighting in self defence, responsibility for one's actions, and it portrays this as a 'deal' or covenant that was made with the first humans. A really interesting book that completely changed how I looked at the Quran is, Logic, Rhetoric and Legal Reasoning in the Qur'an: God's Arguments.

The basic point underlying all the stories and parables is that God made a covenant with the first men, that they would continuously remember him, but each group forgot and transgressed in turn. Therefore God sends messengers as a train to every community, and the purpose of the Quran is to reassure the believers that it's all real and guide everyone to the right path. The righteous are defined right at the start:

2:2 This is the book in which there is no doubt, a guide for the conscientious.

2:3 Those who acknowledge the unseen, and observe the contact prayer (sala), and from Our provisions to them, they spend.

2:4 Those who acknowledge what was sent down to you, and what was sent down before you, and regarding the Hereafter they are certain

2:5 These are the ones guided by their Lord, and these are the winners.

Then the admission rules to 'heaven' are clearly set out:

2:62 Surely those who acknowledge, and those who are Jewish, and the Nazarenes, and those who follow other religions, any one of them who acknowledge God and the Last day, and promote reforms, they will have their reward with their Lord, with no fear over them, nor will they grieve.

This idea is repeated several times. 1. Believe in God. 2. Believe in the hereafter. 3. Do good deeds

Everything else is left quite vague, including prayer and how it's done. To me that indicates that the author was intentionally leaving it open for many kinds of prayer. To Sunnis that indicates that you need Al-Bukhari to come along and record how Muhammad and his followers did everything in an enormous canon of contradictory material.

Anyway I would say that the above is the overall point, not obedience to rules. That may be my own biases talking, but I always read submission as 'acceptance to the truth' rather than physical submission, which is better translated as استسلام

2:148 To each is a direction that he will take, so vie as in a race towards good deeds. Wherever you may be, God will bring you all together. God is capable of all things.

That's not to say that there are no rules in the Quran, but generally the rules are vague and open except for some well known issues like adultery. The 'way of the righteous' is illustrated through the parables about the righteous, like Ibrahim and Muhammad, and that's general stuff like forgiveness, forbearance, patience, charity, etc.