If I may make another small suggestion, RPG and fantasy should be seperated, since their are many fantasy puzzle games, and people could easily make futuristic RPGs. Same thing with horror and mystery. Each game could have multiple catagories, so you search for fantasy mystery. What you would need would be one person (or a small group) to decide length and difficulty, since different people would have different ideas of 'long'. At least if one person did it the length ratings would be in proportion. And no, I don't volunteer.