If you want glorious sunshine and impressive volcanic Greek landscapes, without the crowds in Santorini, then Milos is a good alternative. I enjoyed some great photography, not quite as much as I would have liked but strictly speaking not a photography trip.
In all, a great place to visit but a little too busy for me. Also be warned, the restaurants that score highly on trip advisor will need a reservation for dinner a day or two in advance unless you go for lunch or a very early dinner. The roads aren't great either so getting around is interesting, I suspect a good quad bike would do better than a car would.