You just gave me an idea, what about a game that mixes tennis with pinball! Where you it and aim with a racket like tennis but have pinball mechanics to achieve goals and targets. The concept of mixing pinball with other genres has been proven by the excellent "Yoku's Island Express".
I totally get and support you wanting to finish the game and that all these wacky ideas are totally out of scope. (love the hats idea by the way)
That said I still have to ask: Please add a net bulge + sound effect when the ball hits the net!
It makes scoring a goal so much more satisfying. It can really complete the experience. Trust me, even if its just a simple shake of the goal frame with a simple "thwack" sound it will make a huuuuuuuuuuge difference.
I mainly program in python for work and fun, and I tried to do a couple of game prototypes using Godot Engine. I tried to build some tutorial level stuff in Unity and always found it really clunky and not fun to learn. Godot on the other hand uses a scripting language that is almost the same as python and the UI and engine concepts are so much easier to grasp for an amateur. And it just runs from a standalone exe that is like 50 Mb! The Godot IDE itself is a Godot application! Amazing tool really.