Think that the blackout with tox is a bit anti synergistic with tox builds as tox kills does not count for regen stacks. Instead of 20 stacks required to regen 1 blackout make it 40. Tox kills gives 1 stack and non toxic kills give 2 stacks. To prevent spam there could be a debuff when a blinder hit targets to make it not count for a Blackout regen. Make the debuff last as long as the grenade would have ticked for the toxin to run out. If hit with a second blackout refresh that debuff
Edit: Also show the regen stacks to the buffs hud outside of the meat grinder too.
Edit 2: Seems like the whole thing is just bugged as it is now 
I think it also has a problem with not counting Hyper-Critical kills. The anti-synergy with HC and toxin results in me taking Blackout less often than I otherwise would. Honestly, I don’t understand why “execute” effects like HC and Haymaker blessing don’t count as normal kills in the first place. That should probably just be changed.
I like the thought process behind the OP’s suggestion, but it feels like an incomplete solution to this problem. The reason toxin kills currently don’t count is to prevent self-sustaining Blackout grenades with Pocket Toxin. With OP’s change, there would still be anti-synergy with toxin, just less than currently. Instead, I vote for a hybrid between kill-count recovery and timed recovery.
Here’s the basic idea: when you get a kill (from any source) in close range, it would give 1 stack toward recovering Blackout, and you would get a 5 second debuff to prevent gaining further stacks. The maximum stacks needed to recover 1 Blackout charge would be reduced, probably to around 5-8 stacks, which would mean it takes at least 25-40 seconds to recover 1 charge assuming no downtime from killing. (The exact numbers probably need playtesting to see what feels right.) This would mean you can’t just quickly regain a bunch of stacks toward your next blitz charge by killing enemies with Pocket Toxin, so it’s no longer necessary to exempt toxin kills from counting toward the blitz.
This would also make Blackout less reliant on high enemy density for its recovery, so it would be more balanced across difficulties. It would retain the theme of needing kills to recover, as opposed to most recharging blitzes that just take X seconds to recover. This would also mitigate but not completely fix the anti-synergy with Hyper-Critical, since you only need 1 non-HC kill every 5 seconds to progress toward recovering your next Blackout charge.
Whenever I run blackouts I feel the recovery is just too few for them to be worth it, so I support some quality of life changes for them.
Seems like the thing is just bugged.. Needle pistol gives a stack but the spread does not. Neither does the stim crate. I always thought it was intentional that tox didn’t count because of the nade spam. Seems like they just need to make sure that the target received a melee hit and thats it. Hope they do fix the hyper critical though. I miss not having that in my build always thought it was intentional
My reasoning for 40 was the synergy with the needle tox spread and the stim crate explosion you could easily get 40 close kills. But yeah seems like all of this is just bugged
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