I would love to hear your review of this museum and if you think its worth iti!
Nea Kameni for sure!! Its unlike many things you can see in Greece, super uniqueIf you go to Santorini it is a must see even if you are not in to archeology and do it with a guided tour.
I would also recommend you go to Nea Kameni volcano Island, walk up to the top where the craters are.
If you have spare time take the ferry to Thirasia and have lunch at the waterfront restaurants, the seafood is fantastic and not as pricey as in the main island.