Ok.... maybe I wasn't too clear.
I'm imagining that a reviewer (or maybe even people commenting), can rate "something" from say 1 to 5. Then according to this rating, a corresponding graphic will be displayed, ie. 4 stars out of 5. But I can't expect the users to upload this image.

Also certain mandatory fields such as Title and Author would be needed.
A possible extra idea is to have the ratings of the comments averaged, and showing the two ratings from the home page: one by the reviewer and one from the comments. But this can come later.
The second part of your response, answered my main concerns though... (and it's quite obvious really now that I think about it). The plugin can write directly to the story table and create a story and imbed the graphics. So it's basically just a "review editor" that needs to be done.
Thanks mate,
-Johann