I'm a brony myself and I don't know if allowing horrors is a good idea. I can easily imagine horror stories that are without violence and serious fear, but I can't be so sure about other submitters. I think one of the valors of pony stories that make them so appealing is that their universe is completely devoid of serious negative emotions and their effects. It's what makes the show so cute, sweet and fascinating. When a cynical person, one experienced by the woes of life, usually cold and cunning, watches the show, one can easily catch themselves expecting the use of force to solve some problems, and then the ponies act like they don't grasp the concept. It's naïvety of the universe that makes it attractive and gives people conscious or unconscious hope of living there or at least creating fursonas that do (come to think of it, I guess that makes those bronies/fillies kind of furries).
