
Fuzzy-Wuzzy |

You probably know of the merciful weapon quality already, but just in case, there it is.

Hubaris |

BlackJack Weasel wrote:
theres a trait called blade of mercy. what it does is remove the -4 penalty and grants you a +1 to hit when dealing non-lethal.
Blade of Mercy is a Serenrae specific trait in case that matters.
There is also Weapon Versatility (to turn your Katana into a Bludgeoning Weapon) and Bludgeoner. This also opens some stuff such as:
Cudgeler Style for increased dice size on charges.
Alongside:
Sap Adept if you have Sneak Attack; combined with Sap Master.
Oops I noticed you wanted Traits and Items. I'll take a look, woops!
There is also Sapping to increase the damage by 2d6, but it can only be used on Nonlethal Weapons only... This would be a problem unless you get Merciful and even then its a little suspect.