Alright, where to begin with this piece..
The color scheme you chose fits the signature perfectly. I mean, the color choices are so appealing to my eyes. I've seen this on a few of your signatures and haven't pointed it out to you yet, but the lighting affect you do on the body of your render looks really good. It makes your art stand out, and look a lot better. The butter flys behind Kat Von D's head look really good; it adds a lot of effect. I don't like the small black line that runs on Kat's chest. Although it's probably part of the C4D, IMO you should have erased it to keep the render clean. I'm a little off about the flowers on the button of your piece. It really enervates you piece, in my opinion.
Over all, I really like this work of art, Echoes. I would have to give it a 8/10.
P.S. I like how you didn't cover up the cougar patterned bra.