Miss the old style of traits and perks from the previous Fallout games? This recreates them in Fallout 4 after a fashion (and adds in new additions).
While they can't be directly brought over to the new perk system with its unlimited level cap and new level S.P.E.C.I.A.L. screen without causing some major problems, this mod brought them back in a roundabout way using the crafting system.
Now you just have to craft a specific type of item that grants you the new traits/perks, and you can easily remove everything to respec your character on the fly from the ground up.