We recently stayed at the Athens Atrium Hotel & Suites for 4 nights with the family. Let's start with the good points. Rooms are quite comfortable and the bathrooms have a jacuzzi and hydromassage showers. A huge plus after a long day touring Athens. Breakfast is adequate with a variety of hams and cheeses, breads, cereals, coffee, tea, juice, fruit, yogurt, eggs, bacon. Basic but enough. The staff is very friendly and they are always ready to provide tips on paces to go. The hotel's location is close to a bus stop and there's a mini market across the street and a pharmacy close by. The area is quite safe to take a stroll in the evening. You need about10 minutes by car to get to the Plaka.
The not so good points. AC in the room just changes the atmosphere, doesn't get cool enough. Can't open doors or windows due to mosquitoes and you can hear the neighbors.
All in all, it was a good stay and quite affordable.