For vision, this piece of artwork is absolutely incredible. The colors go in extremely well, and you can see every last detail to the bitter end without much vagueness. It is clearly shown here that you've spent an amazing amount of time on this drawing. For most, this probably left many stunned at the beauty of this. I was, at least.
Originality? Well, sure, I didn't provide five stars for the reason being that a mermaid/sea creature can sometimes be a popular topic. But you took this to a whole new level, enlarging and shrinking things, and adding much more detail and beauty to it. I can say that you made a new perspective of drawing a mermaid.
The technique used in this drawing certainly isn't cliche. You noted that they were drawn with mechanical pencils. But the way you used the mechanical pencils to color and shade and make all of these lines pop out and make some fade into the background, it's really cool. I haven't yet seen someone do the same thing.
Impact? Again, a five out of five stars. I think that this drawing is beautiful in so many ways, and I think that when you first look at it, you'll be wanting to see it in more detail, which you have provided astoundingly for us. This drawing in particular has made me extremely happy to see such raw, original talent.
I really love this work. Please, keep it up.