Hi. I've spent the past several days furiously researching here and elsewhere - thanks to the Greece regulars for all the good info!! We arrive in Santorini from the US on September 4, and although plane tickets and Santorini/Athens hotels were booked in March, we just nailed down the rest of the itinerary, so I am now booking remaining hotels. I delayed for ferry schedules and briefly considered winging it upon arrival, but I really enjoy the research, plus not having to spend vacation time finding a place to stay. Given what I've seen re: availability, seems like a good idea - maybe September is busier than I thought. I feel pretty comfortable with the below, but would welcome any critiques or food for thought.

We are a 40 year old couple. Goals: get a taste of a few locations (certainly not try to see everything), relax - some beach time, but also wandering around picturesque villages, some ancient history, minimize time in crowded/city areas, eat/drink well, read books. My husband rides (and loves) a motorcycle at home, so we will rent one on each island, with a car for Napflio. Other places considered and reluctantly eliminated: Naxos (my runner up), Paros, Antiparos, Folegandros, Koufonisia. Selected the below based on ferry routes and some diversity.

Anyway, getting down to it:
3 nights: Santorini, Oia, Anemoessa Villa - Akrotiri, see famous views, then head to quieter pastures
3 nights: Milos, Pollonia, Niki Savvas - couldn't get a place I liked in Adamas, but then realized Pollonia might be a good substitute for the smaller islands, with advantage of options for visiting other beaches and towns as inclined, boat tour
4 nights: Sifnos, Kamares, Sifnaika Konakia - no real agenda, explore towns and beaches
3 nights: Napflio, TBD - I'm most worried about this travel day, it feels long with ferry + drive, but husband really wants to go here (he went as a kid), we will stop in Corinth on the way, Mycenae, Epidavros, Nemea, wine
1 night: Athens, King George - husband has been to Athens twice and I'm just not feeling cities this trip, just Acropolis and a nice dinner before leaving for home the next morning

Any suggestions/tweaks?

Mel, In my opinion, you got lucky with having to stay in Pollonia rather than Adamas. I prefer Pollonia and is where I always stay when on Milos. The thing I love about Milos is the quiet beauty. Pollonia has enough restaurants to keep you from getting bored but is still so very small and quiet. I love the sea around this area and all the rock formations. I always rent a car and drive all over, visiting every beach on the map and deciding on the fly where I want to stop for awhile. Enjoy!!

Looks very good to me! Have been to all those places and love them! and so nice to end with Nafplio! I'm sure you've consulted the splendid noncommercial website http://www.visitnafplio.com -- click on EVERY section, the info SO good. Do NOT miss walking around the "point" of the peninsula at sea-level path, awe-inspiring. View from park at TOP of point is swell too. BTW, highly second the hotel recommendation of VisitNafplio editor -- Hotel Agamemmnon; its the Only hotel directly on the seafront, and if you are superlucky you'll get a front balcony (side baclonies good too.. on the square). If it's full, look at http://www.omorfipoli-pension.com That's a win-win situation.

Beautiful; thank you both for the feedback! I still need to book Nafplio, so will check out your suggestions.