First you mention Muhammad as the example to learn from. But the only way we know about Muhammad is through the scripture, correct? So are you saying you use the scripture to interpret the scripture?
No, there is something called Sunnah which is different from the Quran.
Quran is the word of God word by word 100%, and on the other hand, Sunnah is the teachings of Prophet Mohamed himself which include but not limited to, sayings of wisdom, inspired actions and teachings, and many other details.
Sunnah - Wikipedia, the free encyclopedia
I understand you might find some difficulty to understand this at the beginning because it's different with Christianity where everything Jesus or his disciples said considered to be part of the Bible and Bible considered to be the word of God.
Muslims believe Quran is a very specific and very accurate inspiration of God, and anything which Prophet Mohamed said and was not part of the Quran, we consider it to be Sunnah.
That's why we follow Prophet Mohamed sayings, teachings, and we are inspired by how he lived and what he said.
Next you mention scholars, cool. Can you say more about these scholars? Are they scholars from shortly after the time of Muhammad? Or more recent scholars? A mix?
Scholars need to cite from Quran and Sunnah and use it as evidence to back up their opinions whether they were from the past or present. Today most scholars depend and cite opinions of the early scholars and seek wisdom from it, because the more a scholar is from the early generation, the closer he is from sources of wisdom, but at some times they might reject some opinions if found out to be less correct than other opinions. They all eventually have to prove their stance using Quran and sayings of Prophet Mohamed.
Finally you mention common sense. Also cool! This gets back to one of my feelings that in fact morals and values exist outside of religion, and in fact they pre-date religion.
How do you define religion? and when do you think the first religion emerged?