ReginaldDwight wrote:Santorini is for sure on the list, but its pretty expensive per night, some of the less popular islands are much cheaper.
That is true Santorini is expensive all year long.
TransportationThe problem with most islands is the bad public transportation, though in smaller islands taxi is always an option and is way cheaper than USA for example. Also choosing an island with an airport will save you time and trouble, on the bigger ones you might find direct flight from the USA in the summer otherwise via Athens or Salonika.
The islands that have airport are: Chios (JKH), Chania (CHQ), Corfu (CFU), Heraklion (HER), Ikaria (JIK), Kefalonia (EFL), Kos (KGS), Leros (LRS), Lesvos (MJT), Milos (MLO), Mykonos (JMK), Naxos (JNX), Paros (PAS), Rhodes (RHO), Samos (SMI), Santorini (JTR), Skiathos (JSI), Skyros (SKU), Syros (JSY), Zakynthos (ZTH)
I would avoid Mykonos, Paros, Corfu, and Rhodes durign the summer as they will be packed and expensive.
Food:All of them have great food. Keep in mind to avoid restaurants in the most touristic areas, where the majority are tourists and not locals, and in the menu you can find all greek dishes regardless of season, plus pizzas, burgers ,etc

You can trust most reviews from Tripadvisor and Foursquare as they are also widely used from greeks, while Yelp is not.
Wine:If you are into good wine, Santorini beats the other destinations hands downs. But you can also consider: Kefalonia, Crete (Heraklion), Zakynthos, or most parts from Peloponese.
Interesting readings:
https://www.winerist.com/blog/entry/best-wineries-to-visit-on-the-greek-islandshttps://www.telegraph.co.uk/travel/destinations/europe/greece/articles/The-top-10-food-and-drink-holidays-in-Greece/However if you are more into quantity, or enjoy retsina (I don't) then everywhere is nice

At 100+ F degrees anything cold qualifies...
If you are into craft beer, the Corfu's 7 island Brewery produces great beer, especially their Citra Blast IPA is world class. Santorini's Donkey Brewer is also very good.
My personal recommendation from the ones I've been, adn based on beauty,sea, food, moderate prices and not overcrowded the first that comes in mind is Milos. And you can also visit Kimolos (15' ferry ride)
Hope some of the info helps.
Cheers,
Alex