Athens

Sounds like a good idea with your limited time. Many cases, these tours allow you to skip lines. Unless you get to the Acropolis early, the line for tickets can be long. Look into that aspect of it. Those are 3 of the important sites. The other site that I thought good was the Old Agora. In addition, the National Archeological Museum is a super place to see the important works of art.

I agree with Paul. You could see these on your own, but it can be time consuming to simply find the entrance gates, and there will be lines (for which you may get privileges with the tour). The sites you mention are all excellent - we visited them in one day, but we also spent some time wandering and taking wrong turns as we made our way from the Acropolis, where we went first thing in the morning, to the Agora. Why not do the 5 hour tour and then add on anything you want to see on your own, like the archeological museum or just wandering in the Plaka area...

Follow the RS city walk in the Greece Guide. The Temple of Zeus and Hadrian's Arch together take about 15 minutes if you want to take photos. RS doesn't recommend wasting time and money to enter the Temple of Zeus sight, you can see it well enough just meters from Hadrian's Arch, another not very remarkable sight. I'd recommend spending a couple hours at the Ancient Agora (just note that the back exit probably won't be open so you'll have to walk back to the main entrance to leave). If you like museums, the National ARchaeology Museum is a wow - allow 3 hours minimum.

I don't know anything about the hotel, but the location is very central, very convenient, just meters from the main metro station, Syntagma, and the airport bus (better than the metro). take in the changing of the guard - every hour on the hour - special pomp and circumstance on Sunday morning. Syntagma is where the RS walk begins.

We followed Rick's audio tour and found it to be quite complete. The tour you mentioned misses some things that we really enjoyed, such as the Ancient Agora. Our stay at InnAthens was great, and it is also close to Syntagma Square. Rooms are modern and immaculate; staff is very accommodating and professional; breakfast was fresh and it includes made to order choices. We took a cab from the hotel to the National Archeological Museum (about 6 euros), and it was well worth our time. Enjoy Athens!

I also recommend using the RS audio guides. We did the 90 min city walk, but it took us 5 hrs as we stopped for lunch, pictures, and made a few wrong turns. Loved it and loved Athens!
Don’t miss the ancient Agora too. Another RS audio guide for that, it was great!

If you decide not to do the 5 hour cruise tour of the Acropolis I would recommend Athens Walking Tours. They were outstanding! We got tickets in advance for the Acropolis of Athens Early Morning tour 8:30 am. We met by the Fresko Yogurt Bar at 3 Dionysiou Areopagitou St. at 8:10 am. That is a pedestrian street right near the Acropolis. Since we were on the tour we did not have to wait in line and our guide Kosta was fantastic! It was a highlight of our time in Athens and I would not have enjoyed the Acropolis as much on our own. If you are interested go to https://www.athenswalkingtours.gr They offer several great tours. If you stay at the Amalia Hotel you can easily walk down Vas Amalias and see the Arch of Hadrian and the Temple of Zeus ruins on your own. To get to the Acropolis area walk down Vas Amalias and turn right onto Dionysiou Areopagitou. We stayed at AthensWas hotel on Dionysiou Areopagitou right next to the Fresko Yogurt Cafe. If you have time later the rooftop cafe of the Acropolis Museum has a good view and reasonable food prices. We also enjoyed the Anafiotika area and the Plaka area.