"Each city was to have its own laws restored and the tribute which they had previously paid to the Persians was to me remitted." – Arrian. He even planned to make an army of his new Persian civilians. He had 30,000 Persian youths to be trained, nicknamed the Successors, to be the next soldier generation. He even introduced some Persian customs to his court, such as proskynesis. "When the Persians meet people in the street. to those of lower rank they offer their cheek and in this way they receive the kiss; but those of still lower rank only make obeisance (proskynesis)." – Strabo. To enjoy a more lavish lifestyle than a " first among equals" ruler here in Macedon. However, he "employed these customs sparingly, and for the most part kept to his exciting practice, fearing to offend the Macedonians." – Diodorus. Showing he hadn't completely changed from the Macedonian ideal of a king, or " first among equals.".
It would seem that Alexander had no intention of completely conquering the eastern lands and letting Macedonia rule over them as upper class, but wanted to tie the nations together, perhaps to prevent rebellions rising up and nibbling at the edges of his vast empire, when it could take so long to just get to the places to put such rebellions down. Alexander did not want to replace every Persian with a position of authority with a Macedonian, but instead trusted the conquered men to know that they had been defeated and trusted them to obey him. Why waste time forcing Macedonian order on them when he could be conquering more lands? This may be what Alexander was thinking.
Alexander certainly had a number of differences from the traditional " first among equals" idea of a Macedonian ruler, especially after introducing some of the Persian customs to his court and had a different logic on the battlefield to that of older, more experienced generals such as Parmenio.