I haven't been to all of them, but I have been to Sardinia, Aeolian Islands (Lipari, Stromboli, Vulcano, Salinia and Panarea), Sicily, Capri and Ischica. There are a few others I have been to that are more off the beaten track, like Prochida, but would like to go to Pantelleria and Isola del Giglio.
Happy to hear any other island recommendations and the best time of year to go.
Happy to hear any other island recommendations and the best time of year to go.