Last year I tried and tried to find an excursion that would not end at the cable car. I thought I had one, but then earlier in the summer those who had been on it reported that rather than the bus taking them back to their point of origin, it simply stopped at the edge of Fira and the driver said “everyone has to get out here now.” People protested that they were supposed to go back on the bus and the driver was adamant. So I gave up on my quest. I wish you luck. I could find no Way to see Santorini without ending in Fira