Hi Sioux,it is a few years since i was in Crete and we hired a car as there is so much to see.
If you are interested in history then this is the best island, also as we were allies to the Cretans they really like English people
As for the weather, it should be lovely as is the food.
If you have time do drive over the mountains to the south of the island as the drive is spectacular(but very scary), we went to the gorge which was a good trip but make sure you have plenty of water and wear trainers as the terrain is quite difficult
Have a great time