We use the quick kill rules v 2.0 - a knife has a 10 % chance of inflicting a critical hit - target goes to zero p and then you roll dmg.
Just as with bullets , melle attacks may only graze the target and give superficial damage.
For deliberate /backstab type attacks gm may increase risk of crit hit or double dmg or some such to increase lethality.
Bear in mind many knife fights end up with a lot of cuts and stabs to the victims before they expire/ are defeated.
Bigger blades - up the dmg and allow for strength bonus as with axe.
We use 1D12 btw to make the game mechanics more lethal..
On our page there are a lt of different melee weapons. Feel free to use in your own game and tweak /alter as you please
www.thebigbookofwar.50megs.com