As MD for our local matches I have had many a stage gamed in ways I didn't think of.
I have found that a good way of catching a lot, is to hang back as setup is being finished and watch the shooters go through their prematch walk throughs. You can usually see if someone has found something you didn't see. Then you can decide if you want to leave it for risk vs reward, or if it will take away 1/2 of the challenge you were attempting to create. Someone looks at the 1/2 upper A zone between the 2-NS that saves 10 steps, I will probably leave it there. A lean around a barracade that gives a full target that was intended to be taken 4 steps futher over, then something gets changed. Everything is relative.