I think you're really getting towards the answer yourself based on the evolution of your questions! Alexander was a conqueror, not an administrator arguably meaning he never had an empire in the first place. The generals that divided up the conquered territory would become the administrators and ultimately shape the rest of Greek history.

But for the short period that Alexander was alive there isn't much evidence of his plans for the majority of the empire. We know that as he conquered territories he would marry his generals to local royalty and those generals would then be in charge. Generally, he never really interrupted the daily practices of a town very much (besides the whole conquering thing) mainly because it's really not a smart practice to completely destroy a new asset.

As for his role with Greece, we know he went on a huge propaganda campaign monitored by his mother that set out to make him a son of Zeus, effectively placing himself in line with other Ancient Greek heroes like Odysseus and Achilles. This very much upset the Greeks for two reasons. FIrst, Alexander tried to assert himself as fundamentally Greek when he was in fact Macedonian and second it was not in line with their myths (that's another explanation for another time) leading to a lot of revolts and instability.

tl;dr we don't really know a lot about his plans, and most of the immediate administration was handled by regional leaders and generals he married off to them.

Source*: Noble, Thomas F. X. "Alexander the Great and the Hellenistic World." Western Civilization: The Continuing Experiment. Boston: Houghton Mifflin, 1994. 33-61. Print.

*note this was just an easy catch all book for my comment. feel free to ask for more books!