THP on kill works great with axe (mainly see it paired with Griffonfoot or sometimes Volley Xbow) or A&F builds but yeah, BH has very, very bad THP generation otherwise. THP on headshot/crit is even stupider on him as he has no way to boost melee crit chance beyond properties. I’d switch that one out for cleave.
For fixing this problem in general: As I posted in another thread, if FS absolutely refuse to just increase the amount of talents in the THP and stagger tiers, to address the THP and stagger lines I’d fuse Smiter with Assassin and Bulwark with Mainstay. They’d need to rebalanced in doing so, Assassin is by far the best stagger talent right now and most careers that can take Smiter over Bulwark/Mainstay already (if they’re not taking Enhanced Power). Perhaps part even needs to be ditched outright (either the Smiter or the Assassin part, I’m leaning towards nerfing or ditching the Assassin part). Bulwark and Mainstay are weaker so I’d simply merge their functionality.
THP-wise I’m not sure what to do with healshare - perhaps move it to a necklace trait (this might be too good, having THP + healshare, so perhaps as a necklace property forcing players to pick between it and health or BCR/stamina? - maybe with the additional effect of reducing THP gain by e.g. 50% on top if you take healshare) - or just outright remove healshare? - either way all classes should have access to THP on kill, stagger and cleave. THP on crit/headshot competes too much with cleave in terms of niche but is very weak right now so FS could get away with ditching it.
That’d leave the level 5 talents: THP on Kill, THP on Cleave, THP on Stagger, and level 15: Smiter, Bulwark-Mainstay and Enhanced Power, for all careers. Now nobody would be limited by THP and stagger talents when it comes to weapon choice, and it’d make future rebalancing easier since FS would be able to see how these talents work across all careers and pick-rates would be influenced purely by viability not availability.