Sports as a theme in general has consistently led to unpopular pins... I can't think of any pin based on common sports that's considered a "really good" pin.
Infomercials? That could actually work, if you did it as a parody...
Ball saver: "But wait! There's more!"
"Has this ever happened to you?"
"Order now!" hurryup
"This multiball can be YOURS for three easy payments..." Lock lit
"Order today, and we'll throw in an extra ball absolutely free!"
Oooh! And the bonus could work in the "shipping and handling" scam... Count up the bonus, then subtract current S&H that eats up most of the bonus (unless you've gotten awards to lower the shipping fee - somewhere there'd have to be a "Free shipping" award )
Physics pinball would be good, but probably expensive table to make if you wanted to have fun with the theme.