extra bleedthrough is an absolute no go, as our bruiser frequently learns, and relearns that the extra 35% bleed through on offensive stance gets him murdered (with nothing directly hitting him in raid, just aoe/surge)
Perhaps I don't understand how your anecdote with Bruiser experience makes it a "no go"? Your bruiser is dying because noone is directly healing / deathsaving him during high surge spikes and his bleedthrough is constant, which is the opposite of the scenario i'm proposing.
High bleedthrough on Necro would only be during the Lifeburn duration - making it a dangerous-to-use tool on purpose since we want to be asking for a stratospheric buff to Lifeburn. I
want Necros to be dying that aren't coordinating their Lifeburn usage with healers and/or using it at inopportune times. I want to consider swapping my CB bardings to HP bardings for increasing my survivability if it means I get to slam Lifeburn more often. I want it to be bad risk if i fire it off without a deathprevent up, or cheetah or equilibrium running. Skill-diff using this ability should produce notably-better results, and what better ability to tie skill-expression to than Lifeburn? For any of these sacrifices and intelligent-usage caveats to make any sense though, we need Lifeburn in
ideal scenario to be
mega-worth the trouble.
And you want a Lifeburn cast to be doing FFU-scale damage because Necros are at moment stratospherically behind assasins and warlocks. Lifeburn = FFU dmg won't bring up necros to assasins overall dps potential, but it'll be at least within reason. And for that steep an ask in ability damage increase, you gotta dangle a juicy steak-worth of sacrifice to increase our take-up chances for the change. Otherwise the easy counter-argument is "well... you know... high FFU damage aint easy, you gotta work for it to be good, mk? you can't just press an i-win button"
Let's have more ideas thrown around if the bleedthrough idea gets enough pushback. But imo Lifeburn needs to be dangerous-to-use since it needs to be mega-buffed, or otherwise we're risking getting no support for it just straight-up get buffed to FFU dmg. The way healing works today, nothing short of bleedthrough route comes to mind to make it actually dangerous. Like VampReq is not dangerous, noone who actually pays attention would buy that argument.