Solo travel in the Cyclades Islands, Greece

Hi guys
I'll be travelling in Greece for more or less the whole month of September this year. I'm set on island hopping the Cyclades but I'm a bit overwhelmed from the information I've read (a lot of islands, a lot of guides).

Some questions

• Which islands would you recommend? I'd ideally like to visit islands with good beaches and an authentic Greek feel. I'm not expecting much of the latter in the tourist hordes of Mykonos and Santorini, but which are the best of the rest?
• Is there a particular ferry company you would recommend? My starting point will be Athens, but are there any options for a multi destination ticket or some sort of island hopping pass?
• Getting around- on which islands are cars/ scooters necessary? If some islands require them will I need an international driver's licence? I have a UK car one, no scooter licence but I know how to ride.
• Accommodation- Any websites that I'm missing other than booking.com, hostelworld, Airbnb would be appreciated.

Thanks in advance