interesting sig, i can see what u were aiming for
here, having a good lighting would make a huge diff
that'd make it so the left side of the sig wouldn't be seen so much
with that you'd get some depth/improve the focal with the just one move

Remember, a good hint to make the lighting is knowing there's gotta be a light source somewhere ^^
Other than that, it's good to be playing with c4d's like that, so keep trying it!
Other than that, the other post i did says what's in my mind xD
KIU!