I don't think we necessarily have any holes (other than the trifecta of suckage.) We can certainly improve by adding a solid bullpen pitcher, an ace starting pitcher, or a big bat, but I'm not sure as to which one we need more than the others.
I can't remember if I put it in this thread or not, but there was an interview a while back in which Dunn was asked about how his homers were typically tape measure shots and he said something like- "hey, if I hit one in the upper deck it counts just the same as when Junior hits his in the first row." Haha nice.