I've noticed something about the slot machine that's led me to change the mechanics of it. Now it's much simpler, as the two machines have been properly fused into one.
The rules are still the same regarding numbers and effects, but now you only need to roll 3d7 once. Since sixes are a possible outcome. I hope this change has made it better, if you have any questions or suggestions on how it should work, then let me know.