Crete is fantastic! I was there 2 years ago, after visiting Athens, Naxos, Santorini, and lastly Crete. I loved every one of those stops, for different reasons, but unexpectedly really fell in love with Crete. It still seems a little wild and untamed, from a nature perspective. The cities and people were helpful and nice, they were not wild . I can hardly wait to go back again and spend more time on the island than the 3 or 4 days I was there.
What time of the year do you plan on going? I was there end of May and beginning of June and the crowds had not set in yet, and it was warm enough to go to the beach for us Mid - Atlantic folks. Although I suspect that even in July-August it won't be as crowded as Santorini, for example.
I think there are some really fabulous beaches on the eastern part of the island that I would look into. We went from the center to the western part, and we could see great beaches that families were going to right off the main highway. We did not do any beaches on Crete because we ended up going to the hospital for our respiratory infections we were fighting and ended up relaxing at our gorgeous hotel pool instead.
I would suspect you could fly into Heraklion and get a rental car or a bus from Heraklion. I found it very easy to drive there, and I was impressed with the bus service to the Chania airport from the main part of the city where we had to turn in our rental car. Looked like there was a pretty decent bus system on the island, based on what I saw at the bus station.
Beaches in Greece are fantastic! I didn't want to originally go to Greece but my adult daughter suggested that instead of going to Amsterdam as I offered. Never regretted that decision and now can't wait to go back!
Frannie