maniac perk is useless on higher difficulties. (Or rather, even on all difficulties.)
So, this mod will make the maniac perk work on higher difficulties.
The specific performance is as follows

All difficulties:.
Hysteria can now stack 240 every 3 seconds instead of 240 every 4 seconds
Hysteria decay redecued from 80 + 60% every 8 seconds to 80 + 60% every 10 seconds

Death wish only
You get 1 damage block from 300 Hysteria stacks instead of 25
Maximum stack of Hysteria is 10800 now
Hysteria can now stack 5000 every 3 seconds instead of 240 every 4 seconds
Hysteria decay redecued from 80 + 60% every 8 seconds to 80 + 40% every 10 seconds
Damage block to yourself is 2.5x (default is 2x)

Death Sentence only
You get 1 damage block from 300 Hysteria stacks instead of 25
Maximum stack of Hysteria is 18000 now
Hysteria can now stack 6000 every 3 seconds instead of 240 every 4 seconds
Hysteria decay redecued from 80 + 60% every 8 seconds to 80 + 30% every 10 seconds
Damage block to yourself is 3x (default is 2x)

After all, you can gain damage block up to 36/90 on DW difficulty, 60/180 on DS difficulty for crew/yourself. ( 25/50 for other difficulties, as always.)

This mod works even as client.

conflicts with other mods that change the Maniac perk.