So you wrote approximately 40 reviews in the span of 14 hours? Do you not see anything wrong with that?
When you write a review, you are really should be doing it for the author since it's he/she that is reading them. It's meant to tell them your opinion of their work, whether you enjoyed it hated it, found it humorous, etc. And that goes not just for Art, but for any medium: Movies, Games, Audio, etc.
Using you last review as an example:
"Pros: -Great drawing -Great Shading"
So what was so great about it? Did the piece achieve it's goal in humoring you, striking fear, driving some emotion, etc. What about the shading? How does it affect the piece? What are some items that are a defining feature of this work?
"Cons: -Kind of bland, colorwise."
Okay, so what colors would make this piece better. Does it need to be lighter, darker, more red, blue, etc. What other items that were off-putting that you gave this piece a 5/10. Was this piece unoriginal, did it not create interest, what are something that you might have done differently?
I'm not saying you have to write a narrative each review, but you have to be more specific. For example, if I was reviewing the Mona Lisa it would go something like this:
"This is a wonderful lifelike piece of a young beautiful woman. I really like the fine detail of her face, especially her half smile. Some of the thing I don't particularly care for are the colors. I think you could have use less yellows and overall it just seems a little dark. I'm also not to fond of the background. I'm not quite sure if that's suppose to be a road or a stream back there. Despite that, this is a great realistic piece and I enjoyed it very much. Keep up the good work!"
A few sentences of what I like, a few sentence of what I didn't, and a summary; that's it. Just from now on please be constructive, because it's the rules.