My team did a helix design in Lunacy, and an open hopper system for Aim High.
The helix design gave us much better control over the balls, but keep in mind that was when we were expecting 10+ balls, this game there's a max of 3.
Here's a video of us testing the helix with a VERY simple construction that we got from another team. It was constructed with straight lines, much easier than bending material into an actual spiral.
This is what it looked like final construction!