Amazing trip at Hotel Thira with two girl friends. Eva in particular made the experience, she is loveliness personified. Room was a decent size and spotlessly clean. Lovely pool area, although it isn't the biggest and sometimes there weren't sun loungers available. We generally did a half day activity every day and then half a day pool time though and we were fine.
There isn't a bar on site but there is a mini market a few minutes' walk away, and Fira and Firostefani are both very close. It would be great if they had a mini fridge with chilled bottles of water available to purchase though, or even a vending machine, as you cannot drink the tap water in Santorini.
Overall would recommend, the hotel only has ten rooms or so and is family-owned.