Hydra is great but it does take a bit of time and effort to get to from the Cyclades. You’ll need to ferry to Athens, then might have to overnight there, then ferry to Hydra. Whereas Naxos, Paros, Milos, Folegandros, etc. would all be one direct ferry from Santorini or Mykonos. If you do go to Hydra then Leto Hotel is a great choice close to the port and shops and restaurants.
Fabulous site Dave! I am taking my daughter to Greece for 12 days in late May 2017 as a grad gift (yeah I know…, I think my Dad gave me a Timex watch, but I digress) and we are flying into Santorini expecting to spend 5-6 days there then ferrying over to Mykonos (not really sure why?) for a couple days. A couple days there and then flying into Athens for 2-2.5 days to inject some culture into what is otherwise somewhat hedonistic trip. I was wondering, after reading about other islands whether it is worth going to Mykonos. I’d love to go to Crete but it seems to be tough to squeeze that in. The original plan was to go to Istanbul for a couple days but it seems really sketchy right now. So is Naxos a better idea than Mykonos? Should we stay longer in Santorini? Is 2.5 days too much for Athens? Any and all info is appreciated.