Perhaps the rating should be split into different sections, such as descriptive level (coving spelling and grammer, etc), plot, interaction (with objects), stability (lack of bugs, I think typos should come here rather than in descriptions, as everyone makes mistakes when typing), originality (the amnesia idea, etc. should count against this
unless an original spin is put on it). This would give the author a better idea of what exactly they're doing wrong, though these scores can be added together into one for an 'overall' score.