Can opnly agree with others, the magical orbs +the recycle upgrade are jsut OP as hell :-) Which I dont exactl mind since it's funny once you got all the mana upgrades and start a new round, you only need a single click and the game plays itself basically :-D
Also for the record the last normal upgrade is like a woman:
claims to only go to 25 but actually goes to 50 max if you click it despite the text :-)
Also a fun upgrade would be something about the game layout, like an upgrade to decrease the big bouncers size, add other (small) bouncers, etc.
you know, to make it more and more like a pinball machine layout.
Also it might be fun to have balls collide with each other.even though that might make it too easy since way more balls might land in the bottom right corner :-)