Kythnos is a nice mix of explored and unexplored: it is not as touristic as many of the other cycladic islands but also not as unspoiled as Kea. Great balance in the middle!
Lefkes is a quiet small place where everything is focused on the beach. The beach is beautiful with shadow coming from trees. It is not organized with sunbeds so good tob ring something yourself
Froso’s seaside house is literally on the beach. In 15 steps (I have long legs 😉 ) from the front door you are in the sea. The sea is clear with a good mix of sand and rocks. Which means you can both play and snorkle and do anything in between.
We lides the house a lot. One airco keeps both sleeping rooms cool. The house has everything you would expect (except for WIFI)