I suspect that if someone goes and spend some days in Thirasia, do some hiking and interact with locals away from the boat excursion crowds, will feel like s/he entered a different world.
But going only for a couple of hours, eating in the seafront tavernas or ride the poor donkeys till top of the cliff and come back down, doesn't really worth it!
These sea front tavernas are not horrible, but nothing special either, and I was very disapointed to see that "beach"-pebbles by the waterfront were full of plastic bottles and all kinds of rubbish, allthough I was there on middle of May. I don't want to think what would be like during high season, or what environmental damage is done by arrogant day trippers in Thirasia or the volcano. Please respect the place you visit! Locals could do more to clean the place too!
As far as concern the donkeys, if you want to go up there and have a look, then move your lazy [--] and let poor animals do what they always use to do: Carry products and people for a couple of times per day, or many times a day only for some busy days per year, but never for a whole summer non stop, without water and under 45 C !
Entering the harbor and looking left, there is a very small church. After passing last taverna and heading to this church, there are a couple of spots that can be used to sit and relax reading a book or looking at the view, or watching small fish coming nearly outside sea. Watch out for large ships passing on the distance. They can sometimes cause such waves, that you can get wet or even drugged away, even if standing 3 metres away from the shore!( the same applies for Ammoudi in Ia)
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC