Playing with Team-Damage and Berserker

Since Berserker seems to be under the magnifying glass, there are two changes which would make him more useful in games where Team-Damage is enabled:

1) reduce the amount of Team-Damage Berserker receives

2) reduce the amount of Team-Damage Berserker imparts to other players

To elaborate on 1), when playing with Team-Damage enabled (probably not something you would encounter on public servers), the Berserker is even less feasible than in normal games, since it's too easy for him to soak up some friendly bullets while holding the front line.
The game already has a configurable team damage percentage, but that applies to all perks equally, requiring a choice - make Berserkers viable vs encouraging everyone else to not pay attention. ;)

The reasoning for 2) is that Berserker cannot easily help a teammate with most of his weapons, since he usually kills both the zeds and his teammate due to area damage or slashing arc. :)
It would help if either all or just the area damage received by other players is reduced a bit (not fully, the same way berserker shouldn't be fully immune to team damage). So, a panic-induced headshot to a friendly player by the sledgehammer could still have full damage, but sledgehammers alt-fire area damage to players of would be easier to survive. Even just a flat team damage reduction would help out.

P.S. I wonder how many people play with Team Damage enabled, and are there any other related ideas. :)

Playing with Team-Damage and Berserker