No one here is really a fan of the Lost Souls set - I’m going to try it with the Grimtools above since having 2 dogs provide good flat RR is really the only way to have the set stand out from other Skeleton builds.
The most optimal Skeleton build I’ve seen is Duskdeep’s Guardian of Death’s Gate Cabalist - he always finds a way to astound me with how much Health he can stack in a build.
Runner-up will likely be my Witching Hour Skeletons build - completing SR 85 easily is no easy task for Skeletons, and I fought Ravager completely blind (despite my longevity with the game, I never fought Celestials before) and won without anything other than healing potions. It’s a very good build with lots of staying power.