I especially love the close-ups of the Batman heads. There is definitley something classical about them that is very appealing. I like your overall style with all of them, but I'm a little distracted on your full-figured drawings because of some proportions issues. Some of this may be purley stylistic and intentional on your part, and if it is, just ignore the next part of the comment.
I scanned the ideal prortiions diagram from Andrew Loomis' "Figure Drawing for All It's Worth," (along with a diagram of Alex Ross' Superman to show how Ross uses the same diagram in his studies). This is a useful diagram when drawing in idealistic proportions. Like I said, if your proportions are just a stylistic choice, ignore this: