When Great Al's dad conquered the city-states of Greece, he knocked them off on his own schedule, or if they came to him, and was victorious either way. That's interesting in another context, which is, during his first few years of conquering Persia, Alexander faced a lot of Greek soldiers who'd either grown up under Persian rule, or were mercenaries.
My guess is, Alexander would have taken the city-states one by one, gobbled them up, and wiped out armies arrayed against him. But of course, we'll never know.
Dunno... Alexander was a collector of sorts. Once he knocked off the local king-pin he usually designated him a satrap and levied the former-king’s army for troops. The further Alexander went into the Orient, the less ‘Greek’ his army became.