I was looking for the rules/guidelines about copyrighted content and didn't know it wasn't allowed until I read another feedback item about it. I feel like this site will attract a lot of roleplayers, who are in the habit of playing in existing canons, using other people's art and photography to portray their characters, etc.. While branching outside of that pattern is a useful creative exercise many should be willing to undertake with your storytelling tools, it should be more obvious that they'll have to do so!