He looks like Diego, but he's actually COOL!
Very fun concept. If you make a sequel of some sort, I would definitely use different characters, because you have tired out any character and plot development with these characters. Also, you may want to consider tightening up your physics engine. The drag (another term for "air friction," which is the amount of speed that is lost due to moving against the air, and unlike normal friction something like a wheel will not reduce friction, only something like a blade, basically, the less of it the object, the less of the friction, incase you didnt know) and the force that the arrow shows is often misleading. Other than that, great game.