There was a great deal more than organ playing going on. On April 4, 1904, a daughter was born to Karl and Hertha, “opus 1,” as Reger affectionately called her. Elisabet Straube's life began in the tide of optimism brought on by marriage and the move east. For whatever reason, further children were not in the couple's future, though there is evidence that at least Karl had hoped for a boy as a second child. For now, though, the clan of three on the Dorotheenplatz was happy and Karl was immersed in his work. He had a family and a prestigious position. He got on well with Pastor Pank and Thomaskantor Schreck. The letters from Reger arrived regularly, and Straube continued to write essays on behalf of the composer. And even with the new baby, Hertha helped with her husband's burgeoning correspondence and managed the family finances.

In her study of the Leipzig Conservatory during the Nazi era, Maren Goltz has proposed the term “Straube system” for the tight nexus of influence Straube cultivated over Leipzig's art culture by the 1930s. If anything, that notion can be expanded. It is true that, in the decades following his move to Leipzig, he steadily worked his way into the sinews of the city's musical institutions, over which he projected a more or less unified cultural vision with explicit elements of religion, Darwinist history, and politics—a vision that in some sense may be described as Kunstreligion, as Goltz does. Straube's influence came to extend well beyond the official capacities he exercised at any one time to close relationships with other key cultural actors and students. But Leipzig was not the only site where Straube's monopolization of influence played itself out. This way of operating had been foreshadowed in his dealings with Wesel, where he had rapidly branched out of his organ loft to integrate himself into that city's musical life. In Leipzig as in Wesel, the organ would not present a sufficient horizon for him.

For his part, Straube was hyperaware of his stature and ever-accumulating authority, which he sometimes expressed in a tone that could be heard as pretentious by those who felt unjustly disenfranchised.