Perhaps the image names could be dynamic (like rate1,
based on the rating. I did this with the rating names too (like
"accurate", "well sourced") to make it easy to add on to.
At the moment the images are integrated with css , so that you see the
text if css is not enabled (screen readers etc.).
I am actually not that sure if replacing the spelled out version with
icons helps that much - maybe have additional icons, or do something
with color would be good. But thats really not my topic - my designer
told me to better stay with black and white. But I could ask him, maybe
he has an idea...