Just came back from there, amazing place.
Also Korcula next door is incredible, really laid back.
Some tips for Hvar... if renting a scooter or boat I used Antonio rent, the guy Juri is as sound as they come an everything spot on. Took a ride around the island then rented a boat from him the next day all for about £60, was well worth it though.
There's a restaurant called dalmatino, probably best service I've had anywhere.
If you like wine go to Tomic winery in Jelsa, the wines are great and nearby fishing villages are really nice, especially after a few glasses!
I'd probably try to avoid high season as I heard it can get a bit packed and it would be a lot different, so April-june, September-October probably best times to go if you can.
Only place I didn't like so much was Dubrovnik as its crazy touristic, much preferred Split, but everyone is different and although I loved Korcula some would find it a bit quiet.
The people in Croatia are genuinely some of the nicest I've met anywhere in the world, also around all these parts of Dalmatia it is incredibly safe.