PW in oly? sheesh, someone is not going to have fun times
as far as i remember, i was +4 str -4 dex, +8 wit -? (i dont even remember which mage dye is restricted, but you can put only one, i think it was -INT that fighters can remove?)
however, if you are not used to general caster dagger type (casting slow, heal, hex, power break, drain, ...) and going for more burst dmg, i would suggest +8 str -8 dex (or if you feel like you are missing a lot of blows, kappa, you can go -4 dex -4 con, but i wouldnt dare to lower con on pretty much any class )