Okay, let's have the basic, cliche Greater Germany scenario, where all of Germany is united in 1848 after the Frankfurt Convention.
But what if, instead of Hungary, Croatia, Slovakia, etc. being detached from the empire as is usual in the cliche, what if they are incorporated into Greater Germany after a dose of handwavium?
Assuming (and this is, admittedly, a big if) they can keep the minorities in the empire, what happens next?