For your consideration:      A leader board would add some "competitiveness" to the game and give players a reason to play more. Right now, the game feels like its in a vacuum.      I think adding a few additional game modes/options would be nice: using additional or modified physics to change some aspect of the game (i.e moon mode, magnetic balls, etc). A timed mode (which would go well with another leader board), would be nice. Something with some ramping difficulty might also be a...