Oh man this is great, I had similar thoughts several months ago. Strenuous diplomacy between Lydia, Egypt, and Persia prevent an outbreak of war. Having a stable multipolar Middle East could engender trade growth, perhaps shifting Persian focus southwards to the Indian Ocean. Instead of wasting lives and treasure in Anatolia and Greece, the Persians focus on building up their own country, eliciting the earlier development of the Silk Road. With Athens having to contend with the less threatening Lydia, they would have less sway over other Greek polities, and perhaps Thebes and Corinth come to an understanding. Instead of a Peloponnesian War a Corinthian League is able to cement control over Epirus, Cyrenaica, southern Italy, and Sicily. Carthage solidifies its hold over Numidia and Mauretania and in the process creates a thriving agricultural state. With a strong Greek presence running interference in the western Mediterranean, the Turdetani establish themselves as the dominant power in southern Iberia. Southern France is disorganized but eventually comes under the sway of the Arverni. Republican Rome's westward expansion is stopped at Liguria. Macedonia doesn't gain traction, and so Alexander never makes his march to India (shed a tear for Bactria). Sea trade ties the region together in general peace probably until the First Century AD. Perhaps having a better trade system set up with Persia and Egypt prolongs the Mauryan Empire.
Overall, better human development and potential for scholastic achievement. Well, I can hope at least.