Hersonissos is quite lively, but we went in June last year too and it wasnt too bad that time of year. It only gets really lively in the early hours. I would recommend going to a restaurant called Galini, it is fantastic food and service and if you have children they are brilliant with them. Star Beach in Hersonissos is also very good. It is a water park and beach. Free to get in and you just pay for the activities you want to do! Only 3 weeks on tuesday unitl I go. Hope you have agreat holiday. If you want any other tips just ask