Loutro is a small place (you can walk from one end to the other in 5 mins, max), so really any accommodation is central :) That said, I'd argue that the Molos Apartments are an excellent choice as they're design-forward, newly renovated, and a bit up on the hill for the best views of the village. Hosts were accommodating, and the beds were comfortable. Washing machine for clothes was a nice touch.