Ok, render crits:
-Rubber is way too dark, give that some blurry white highlights with grain in it.
-You need strong(er) key light, looks like just GI now.
-Are you using falloffs ? Your reflective materials look a bit too standard/fake CG, don't know how you would go fix this in C4D, but good falloff settings will probably do a lot.
-Camera angle is a bit boring
