Our niece lives in Alonissos and we went to visit her and her husband, who is Greek.
The island of Alonissos is beautiful and not at all commercialized. I liked the food at all restaurants,it was really magnificent and fresh, tasty and beautifully delivered with great white wine. Especially our visits at the bakery were a must. The small specialty shops had wonderful gifts, too! Generally, the old town is really worth to visit for food, gifts and the beautiful view to the sea...
The best beaches are found mostly at the northern part of the island. There are many hidden away beaches to visit, swim and catch the sun, you should only take some time to discover them!
Our hotel there exceeded our expectations, since the accommodation was first class with views to match. The owners were very gracious and the pool was an everyday must, like the breakfast and the early morning coffee, delicious! It is more than possible that we will come back to Alonissos!
Something that should be better, though, is the access to the island from Athens.