First, I think they are both great drawings. If, as you say you were going for the comic book style, you’ve probably got it.
I’d just add a couple of nitpicks, nothing too serious:
1st drawing of the black girl (I assume she’s black because of the afro ) - the right shoulder seems too big(I know there’s armor, but it seems unbalanced), and the left hand seems to need a bit more work.
The 2nd drawing - well, maybe just her breasts, they look a bit strange, and perhaps her shoulders too, they seem a bit too big. Aso, the shading is a bit strange, particularly on her arms.
Anyway, it’s easy to criticize, but hard to create, so in all, I think you did a great job.