I don't know daggers seem to do piss poor damage if you attack any were but the back (at least in classic mode).
If you nerf flesh sacrifice it will make other builds gimped the ap allows me to use battering ram to get a slow knight close enough to be of use and the damage to get the armor down which is always really high. How about not being able to use Adrenalin rush on same turn as flesh sacrifice or maybe take heavy bleed damage if you do on same turn as you have just but your self.
I agree that backlash needs to be 2 ap as it moves and damages and that throwing knives should be changed to 2 knifes instead of 3 and make them pierce armor but with lower damage.