Theres no point having both the knife and chainsaw if they both do 1 hit kill, so the chainsaw should take 40% of the life for every second its in a solder or something like that.
This should give the knife a real purpose instead of the 'cool' factor.The B.VEST should block must of the damage from both weapons.
In real. MODE the chainsaw should be 1 hit kill like it is now.
Give the knife aiming like the chainsaw.
The LAW is fine as is.Dont change it at all.