Too big, It's hard even for me to make something cool with that size without making allot of mistakes. As i said earlier in the other topic, make a very small artworks, and don't resize them when uploading them on servimg.com, change the option to "No".
Change the system to "points", width 400 x 150 length. As a start, it's the perfect size. Try not to make the colors strong as it is right now, sometimes strong colors or strong lights doesn't feel right when looking at it after few seconds.
Yea, you fix the size and try again, you should get a better result. Also move the C4Ds around and try to find a focal point, create a flow, or both. You can resize both of your render and your effects using ctrl+t until both have a suitable look when placed together.