With comics, my greatest strength is clearly character design (I'd say 70% of all the art in my computer is just character designs):
And when it comes to writing, I'm best at doing interactions between characters. Humorous ones, dramatic ones, or anything in between; when it comes to just making people talk, I'm yer gal.
I'd guess if I had to generalize it, my strength is in the specifics of a story: the nuts and bolts, all the little things that come between point A and point B. How the characters look, talk, and move, and how that all comes together to achieve an overall effect; that's the kind of stuff I love to figure out. ^^