Dark-Boy Final Apocalypse Saga Wallpaper #1

Well this one took a long time. It took me a day just to get the anatomy right (I almost gave up!). This is my first time drawing on a massive sheet of comic book art board paper. And holy crap, the results! Only problem is that the paper is too big for my printer/scanner, so I had to have it scanned at school and emailed to me by my teacher! But this paper, just... wow. That's all I can say about it.
Still feels like something's missing from this piece, but I can't put my finger on it.
This (sort of) depicts a small scene in one of the later novels (I have the entire plot written out) during a major battle, to which Damian and a few others have arrived to support those who've spent days fighting it (hence why Jenny's all beaten up (and yes, you pervs, her panties are partially visible -____- xD)). The sign with the skull and bony middle fingers crossed behind it is the flag design for the Dark Bros. Rebellion that is later established to take on the world (and I do mean the ENTIRE WORLD). The yellow (well white, I guess) tape that says "STAY THE F*CK OUT" is just me fooling around.
Creative critique and opinions are most welcome, as always!