Billy Yargas gave a talk at Gamemasters in Quincy. Il a couple of years ago. I was just starting to build then and ask him some questions after. He was super helpful. But the thing I remember most was he said if you make a call and its not quite right, put it away for a week, a month , 6months or a year or whatever. You might get it out sometime during that time and it will be the best one you ever ran! So if you make one that looks right but not quite there, hang on to it!!