Let me preface this by saying I am not usually a fan of mods that make the game easier, but I also think if it makes a game you own more enjoyable for you, then go for it.
I was getting tired of direct, on target shots from both flippers getting rejected by the scoop. I draped a piece of cloth (actually 2 pieces doubled over, so 4x thick) in front of the scoop opening. I used a thin cloth you might use for cleaning eyeglasses or cell phone screens. I hung it from a zip tie attached to a nearby post.
The idea is to absorb some of the ball's energy before it hits the scoop to reduce the chance of a bounce out. It actually works very well. I want to play some more games with it, but in the few games I played, I made almost all direct shots, even from the right flipper, something which was nearly impossible before on my game.
That being said, it's definitely ugly. I think a thick piece of thin clear plastic would be almost unnoticeable. A metal flap (like used on one way gates, but able to swing freely in both directions) would probably also work. 20190314_174945 (resized).jpg