First an observation: spoiler photos seem almost to be the sole preserve of Dartmoor caches. In almost all other regions I have cached you hardly ever see one.
When I started placing caches I stated no spoilers and no hints. My coordinates would be good and I would not place micros so there was no need. Then I thought that most of my caches are deep in the moor and once somebody has walked 6 miles they deserve to find the cache, so I added spoiler photos. Trouble with that, it was abused. It identifies a spot so accurately that instead of posting DNFs, cachers were posting Needs Maintenance and some even replaced my cache and logged a find – a practice that I do not agree with. So I am now back with no spoilers and no hints!
I guess the situation here is that, like everything else in life, there is no one-size-fits-all approach to geocaching. Odd though it may seem, I really don’t like searching for caches – I got into geocaching because I enjoy walking, and I like to visit new places and see great scenery. I do appreciate clever hides, where some effort has gone into concealment, but I’m not a lover of grubbing around in leaf litter for caches, so I always use every scrap of information that is available before getting to a cache, which includes all hints, photos and previous logs, to minimise the amount of time I have to spend searching. Because of this I usually try to hide my caches in obvious places, with hints and spoilers for those that want them.