Um...none of the above. O.o
I still think your original idea of sending letters or something to Mina and Naka <I>saying Darlig is doing these things (but really isn't) is worse. I know that I, personally, have had enough of torture and stuff to last a long time, otherwise for me it just gets...repetitive and predictable, especially if that's what the entire storyline is focused on. And I think that messing with people's minds is worse; it'd be really bad, IMO, if Darlig tried to win Vai over. And more unexpected and twisty. >_<