Definitely needs to be smaller to match the ship's scale.
What do you think of a flasher mod that highlights the left rear area between the ships when the ball is in the cannon waiting for you to hit the button?
It might be nice to have more of "attention grabber" that let's you know you're cannon is ready to fire. Similar to strobing flashers on Houdini that indicate the catapult is about to fire. Lightning effect maybe?
It could be useful to alert you during multi-ball when you might not be focused on it.