Not reaLLy sure how things work anymore.. but I used to go with an eLementaL on the off hand..
use damage reduction card on your armor when hunting MVP's.. I think that was the ALice card..
damage cards on the right hand ofcourse..
aaand, enough dex to make 400-450 hit, enough for pretty much aLL mobs. Makes getting max aspd easier too..
as I've gone the way of the katar in this server, Im not reaLLy sure how this wouLd work out for you..
I've seen some guy pwn the Lhz3 MvP.. he was critting it for Like 15 or 18k per hit. >.< he was on katar though.. ILL be watching this thread with you, since my main wiLL be an assasin as weLL. :)
Good Luck.