Stayed a week on 4th floor, room facing Ermou St, wonderful experience. Having this exposure allowed us to hear street performers and then close the glass balcony door.
Amenities: comfortable bed, robes, minibar, fridge, Nespresso machine and coffees/teas, sofa, writing desk, TV, 10th floor restaurant for breakfast (very good), brunch, and dinner (with lit Acropolis in the background).
Very close to Syntagma Square with metro and bus lines, local Starbucks and McDonalds, Public (multi story store of books, electronics, stationary, games, etc),walking distance to cafes.
I also want to mention the Concierge who often was standing in the lobby to help guests. She gave us advice on cafes and restaurants, using the transit system, made reservations for us.