Probably early September would be your best bet temperature wise. We are in our early 50's and loved Argassi in Zante, Kos town - obviously in Kos, & Kamari in Santorini. We are going to try Lassi in Kephalonia for the 1st time this year.

we usually go in may and october temps in mid 70 are common, been to Zakynthos[Laganas and Agassi] {don't let Laganas being the party capital ..if you go in may and chose a hotel to the east of town you won't get any bother we like the Mediterranean} Crete Sissi and Agia Pelagia. Kos Kahdamina again if you go early in the season you will miss the party animals] Chalkadiki but not too late as being further north it gets cooler towards october.

almost all the islands will be around those temps. in may/june late sept/oct

yasus
wizard

Thank you both for your replies. It gives us something to go on.

We've been to Khardamina & Laganas as well & really enjoyed. We were fortunate to stay just at the end of each resort as we were there in August.