The overall concept of the piece is nice. However, I'm not sure about the c4d render you chose. It seems a bit "heavy" for the rest of it. Meaning, it just seems a bit out of place with all the vector. It also appears that some edges seem like they need some anti-aliasing. Maybe go back over them and feather it at like .3 or .4? Colors seem ok, but just a personal preference, I guess.
Effects and colouring look pretty good but the c4d looks out of place and theres no obvious focal. Try blurring it all a bit.
http://en.wikipedia.org/wiki/Anti_aliasing Can't tell you how to do it in photoshop. But when using the pen tool, feather it at .2 or .3 to help reduce it.