I realize that you are probably close to done with this project, so forgive the late suggestions. Labels on the power and accuracy bars would be helpful, and a putting mechanic when the ball gets close. (maybe take away the arc of the ball once the player gets within a two block range?) These two additions would make the game feel easier to pick up and play. I was hesitant to make these suggestions as I can see the joy of experimentation in your games. I don't wish to mess with your creative process. Especially since nobody else is making unique high-concept mini games like yours.
I'm always happy to receive feedback; feedback is a surprisingly rare asset.
If you decrease the shot arc to 0 degrees, it is effectively a putt, but I agree that it's not very well communicated. Maybe a "switch to putting" button would feel more natural?
I'll take these suggestions into account when I pick this project up again. Thanks as always!