Go to Istanbul. A massive city, teeming with people. From the ship you can watch all the ferries swarming to their various destinations along the Bosphorus.
Cruise ships berth near the Golden Horn area with all the major sites - Aga Sophia, Blue Mosque, cisterns, Topkapi Palace and Grand Bazaar.
It is easy to walk or get a tram over Galata Bridge and do exploring on foot.
Kusadasi lets you take a tour to Ephasus, which is very intesting.
If you arrive a day or two early in Athens you can explore the acropolis and Parthanon and the other ancient sites.
Option 2 for me!