So maybe drop nunchaku back to what I had for the saingham originally (2d6 damage light weapon with a decent crit), making it the go-to weapon for pain? Makes as much sense to me as anything else.
Being able to apply a bonus to AoOs seems like a cool effect that would be nice to add, and I think I will add it to the options, but like bonuses to bull rush, grapple, and sunder, I don't want to add it to any of the core weapons. I think I will add that to the list of potential abilities that you can add in for .5, like bonus to combat maneuvers, as a masterwork weapon, and now that I think about it, a bonus on crit confirmation rolls also seems like a good option to add to that list.
Well nonlethal damage normally imposes a -4 penalty, and there's only one core weapon that ignores it. I guess I could make it .5, but then what would the sap gain for that extra .5 points leftover?Ah. That makes far more sense, and there aren't really any other easily-observed abuses. Only other thing is that I don't really think 'able to do nonlethal damage' warrants a full +1- maybe a +.5; it's not exactly as strong as a Reach weapon, after all.
edit: Random thought-what if nonlethal damage were free, but the ability to switch between lethal and nonlethal at will costs 1? That way the sap doesn't have to deal with half slots, as it's nonlethal only, but someone who wants a masterwork greatsword that is forged in such a way to make hitting someone with the flat of the blade not totally unwieldy, they have to pay for it.