I've never been to Thassos, but we visited quite a few islands in Greece and loved them all. Our favorite one that we went back to many times was on the west coast off the mainland: Lefkada. We loved to go there windsurfing and then unwind at night in the small village/town of Vassiliki. Those were awesome times! And your photos reminded me of them. Thank you for that.
With the greatest pleasure! My son has been to Lefkada many times and has the same words of praise. As you say, I think all the islands in Greece are equally simple, natural, beautiful. I only went to Thassos because it is accessible by car from Bucharest, where I live. About 800 km.