Loading JustGameGuides
Factory Operative leads, and both Fisherman perks sit at the bottom doing nothing.
Data updated
Every node a zombie holds uses one red-skull slot, mastery nodes included, so each perk is competing with all the others for room. Factory Operative reaches 63 recipes, more than any other perk, and shows up in both the Building and Smithing trees. Buy one. The two Fisherman perks cost 200 and 500 green and do nothing.
Perks are ranked by what one slot buys: ticks saved, mastery gained against the locks of the recipes it reaches, output formulas, how many recipes are affected, and the tech-point price. The musician perks sit higher than the data suggests because the game's code reads them. Perks with no effect go last. Placements are checked against each game build.
Perks from all five trees side by side. Remember a zombie can only work one station.
Every perk against every other, one slot at a time.