The mystic machines (those electric bathtub looking things) were a cool concept back in early SN. It would be cool if we could have those back.
There could be 3 mystic machines in each map, each with a different buff for the neighbor. One could decrease ability cooldowns, one would substantially increase stamina, and one that would give you more health.
Mystic machines would be a good re-addition to the game because it would make neighbor players want to increase their stats first instead of instantly transforming, it would also make the neighbor get stronger as the round progresses, but not to the point that neighbors are weak if they don't decide to activate the machines. Mystic machines might balance the power between the kids and neighbor, because right now the kids can be more powerful than the neighbor