5/10
It seems as though there wasn't much thought put into the creation of the vectors in this piece. Pretty much all of them just look like a circle that you took a chunk out of to make a moon :P. The bg reminds me of old style fractals or grunge brushes. Also your text really doesn't fit, more like slapped on with a drop shadow.
- A creative way you could do your text, since this is a vector styled piece, is use some unique vector designs to create your text.
your second: 5/10
I don't know if you chose to or not but your render doesn't look like it has been cut out properly. I can still see it surrounded by a white thin line. And if you did chose to it just looks bad XD.
The design the the bottom left corner should also be removed since it doesn't enhance anything and just draws away from your focal point since it's brighter than anything else in your sig besides the bit of red on the hand. The lighting also seems off, the light source on your render seems to be coming from the bottom, yet you have your lighting on the bg coming from the top.
The circle that repeats your render's head next to your text doesn't really do anything, IMO it would go better with just the text. Also moving the text a little ways away from the right side would help balance things out since it almost touches the side of your sig.
lol and sorry, I hate just rating sigs since that doesn't teach you much, and I think I went a bit overboard on a few things since I haven't posted in quite some time :P.