This was lovely! I really liked the banter, though some of the speech bubbles ended a bit too quickly. I like that there's variety in the levels, each one had a twist that I felt added to the complexity and enhanced the overall experience. 
I think the throwing levels should probably have a limit on how many you can throw, otherwise the player can spam and win by sheer volume :P Though it is very fun to fill the screen with infinite bouncy balls. 
Overall, great work! 

Well done on this game! I had great fun launching a volley balls at my opponent :) More levels would be cool to play further. 

Really unique and good idea really could be a interesting game. I think a little more work needs to be done on player feedback, I felt playing with the sliders while a good idea was a little hit and miss and I felt like it was more that I got lucky than actually "solving the puzzle" partly I think the controls are too sensitive so even slight deviations made the ball go in a very different direction, and I feel adding to many sliders didn't really add that much, I feel just adding the sliders in each puzzle that help solve that puzzle. But otherwise a really good game and good luck with the Jam :)

Neat game well done - I would have liked if the music was a bit longer - good job well done

Putting the player in control of the gravitational settings is a cool idea.

I did find myself not knowing whether I've set the gravity to negative or positive so I would've like to see a notch on the gravity slider to indicate where the zero value is (I assume that adding numbers would not have mixed well with the aesthetics).