I like the base idea, having to think of paths for both characters was a nice touch. However, there were a lot of implementation issues which detracted from my enjoyment.
I don't think the association between the characters and the goals is clear, because both characters have the bright and dark color. It took me a long time to understand what to do because of this.
The 'overhead' character is a little annoying to control because if you go off path once you have to restart the whole level including placing paths. It would have been good if falling off the path with that character just sent you back to the start instead.
I think the game would have been better served with a grid system for the paths. This was a bit too finicky for my liking.
The presentation could have used a bit of sound.
Overall, I think this is a fun concept, but the implementation had some problems that heavily detracted from the gameplay.