Thanks. Staying on the mainland does make more sense than dealing with unpredictable ferries. Larger islands do have several flights per day from Athens, though, and you can't beat Santorini for spectacular views (and some hiking and archaeology thrown in). So I'm thinking maybe a few days on Santorini and the rest of the time in Napflion as a base for exploring the Peloponnese.

Where would you want to spend Christmas - Athens, Napflion, or Santorini?