This turned out to be a really nice place to stay, both in terms of what it was like to hang out in the space itself, and in terms of location. The AC was effective (very important in the summer), and there are seating areas on two different sides of the cottage, so you can get shade at different times of day -- one of them has an ocean/sunset view. You're far enough away from downtown Oia so that you're out of the crowds, but close enough to walk in (either on the road, or on the Oia-Fira trail, which is about five minutes walk away uphill, and in my view, one of the nicest things to do while you're there). You're also basically across the street from a really nice restaurant, one which wasn't mobbed in the way that the places in town were, and was a nice place to hang out. --Oh, and on that topic: I'm generally suspicious of restaurant recommendations from a hotel (too much possibility of arrangements :-)), but our host's recommendations actually turned out to be the best places we ate at, and we tried a bunch.
Long story short, I'm pretty enthusiastic -- I'd come back, for sure.