I built a specially engineered tree house in the oak tree in my back yard and put it there, who would think to look up there for anything other than a leftover PB&J....
I simply don't worry about it. The reality is any burglar that has the ability to get into a safe is hitting safes in neighborhoods that the very wealthy live where there is a real payoff in cash and jewelry. Your regular burglar is looking to get in and out as fast as possible. The longer they are inside a house the higher the chance of getting caught.