I’ve made a Witching Hour build that was more suited for fighting high SR, consistent (if slow) Crucible times, and fighting Ravager. Here is the build. Like you, I wanted to see how hard you can push it when you stack flat damage as high as possible.
I’ve also made a Chaos Reap Spirit build which doesn’t have Skeletons at all, but instead plays a hybrid set-up with the Black Scourge critters and Bound Spirits. I think I’ve been able to beat Crucible with this build one out of 5-6 times.
If I had to suggest nerfs, I’d suggest nerfing the RR from Fiendgaze Tome from 15% to 10% (which also helps nerf the Chaos Conjurer) while also slightly nerfing the speed bonus from the Lost Souls set. Maybe a slight nerf as you mentioned about the Skeletons special abilities, but I wouldn’t go overboard, especially as Sigatrev is likely fishing for the perfect Skeleton combination to make these runs possible.