Travel Review: Greece Trip, Athens, Milos, Naxos, Acropolis, 10-Day Tour

In flight entertainment is one. The airline offered it, but we assumed it would be integrated into the plane. It was not, and you had to download their entertainment app prior to departing. It's a long flight to Greece, and we didn't have entertainment going over. We made sure we had it coming back!
The ferries to the Greek islands can be lengthy (our longest was five hours returning to Athens). The larger ferries do not have seat assignments, so it was confusing with no guidance from crew on where to sit or where to store your bags. Also, lots of smokers on the boat who bring smoke inside with them, so if you're sensitive, you may to consider flying to the islands.