I agree that it doesn't matter how many people believe something; rather, it is whether the WORD OF GOD teaches it.
As to your understanding of Luther's theology, I do not see it that way at all. A lot of what Luther believed was frankly still quite Catholic. His baptism of infants, for example (which Calvin also held to); and a slight variation on the eucharist (almost semantics but not quite in comparison to say Zwingli's view concerning Lord's Supper) all showed Catholic influence. He also seemed to be quite informed by Augustines views on things in many areas.
Where Luther differed was in what you call the "notion" of salvation by faith alone.
Contrary to your assertion, these theologies do not fit modern man; for modern man's invented religions ALL without exception create a salvation that is at least in some way shape or form dependent upon MAN being good enough in some aspect of life. Luther recognized man as a lowly worm incapable of pleasing God on his own. And, he used Scripture to back it up.
Annalex, I will repeat what I said before. Please pick up the WORD OF GOD itself - exclusive of commentaries by Catholic (or Protestant) theologians. Look at it. Let the Words tell you what they mean. You will not come up with a theology that is too far from Luther's on Salvation.
That would assume that the Scripture alone is sufficient for faith formation. It is not, -- the scripture itself says so, many times.
Thinkest thou that thou understandest what thou readest? Who said: And how can I, unless some man shew me?This being said, I am firmly convinced that anyone who reads the scripture without the Protestant conditioning will end up Catholic or Orthodox, at least in matters of soteriology and ecclesiology. He may not become a great marianist, because Marian devotion is a mystical experience rather than a direct result of the study of the scripture. But he will cease being Protestant.(Acts 8:30-31)
How then shall they call on him, in whom they have not believed? Or how shall they believe him, of whom they have not heard? And how shall they hear, without a preacher? And how shall they preach unless they be sent?
(Romans 10:14-15)