Great podcast!!
Since you are already converting the heads of the castigators to be different, just change the bow tips from the castigator ones to something similar (or just cut some tips off of some random swords/spears) Make one have a fancier point and your conversion is done for Judicators, you will just have the crossbow ones.
Great Idea on the +1 to save buff, but also look at Sequitors, they are liberators on black tar heroin. Stuff as many Big hammers as you can (3 per 5, or 5 per 10, or 9 per 20).
They always get +1 to reroll with shields, can choose EACH Combat phase whether to re roll saves or hits. They can be battle line with a lord arcanum as your general.
Also, look at this dude: https://www.games-workshop.com/en-NO/Lord-celestant-Gavriel-Sureheart-2017
His command ability is add 3 to charge phase for every stormcast unit within 9. (MUST PLAY HAMMERS OF SIGMAR FACTION)
Drop him in with whatever unit you want to beat face with, hopefully with 2+ command points.
Use his command ability 2-3 times during the charge phase. Add +6 or +9 to your charge...thats right, auto charging for units within 9 of him at the start of the charge phase.
Good luck!!