Maybe I’m in the minority but I don’t think the bearer thrall HP needs to be reduced. They don’t tend to do much damage so even with really high HP they still get destroyed by bosses in my experience.
It makes sense that they can tank standard enemies while I farm for brimstone in shattered springs but also are bound to get beat down if you get too close to the Rotbranch. I feel like that’s a pretty solid balance already.
That is not the intended vision of the Bearer NPC's use, but we also overcorrected in the Chapter 4 update so we're walking that back. Further tweaks will likely be made in the future, but will have to wait for a new feature we've been working on first.