Ormos Livadhi at the south-east corner of Serifos is the BEST place in the Cyclades
, s good anchorage or harbour berth if you prefer; then take the bus up to the Chora and walk back down the hill - it's everything Mykonos Town tries (and fails) to be.
Not keen on Mykonos - horrible harbour and the town's too 'Disneyland' and totally geared to the cruise-ship market; the nearby island of Delos is well worth visiting though and whilst you can't overnight there, there's a great/secure overnight anchorage a further 2M to the SE at the bottom of Reina Island.
Liked Naossa at the north end of Paros and if you fancy a full day ashore, I'd recommend hiring a car and touring Naxos Island.
Be wary of the cute horse-shoe shaped bay at the SE end of Sifnos (I can't remember its name) which gets rave reviews
in all the Pilot Books
, as the swell often rolls in making it uncomfortable.
If you get caught with a Meltimi period and sailing's unpleasant, consider catching a ferry
(from Paros, Naxos and probably Mykonos) down to Santorini/Thira for the day.