I actually really liked that second image and I'd be interested to see if you could turn it into something more militant combined with my initial criteria.
the guardian is a custom render that I made using milkshape and 3dsmax. The girl is Kikyo Osana from the anime Project Aegis Zero. Didn't do too much from the original picture except a few enhancements and some cleaning.
Originally I was going to use Tōko-sensei from Negima! but she didn't fit the dark hair criteria.
Personal notes: I'm going to have to change "Liberty Navy" and Rachel Baker to either different fonts and/or change the color scheme.
Ooh, I really like this, though I agree with your 'personal note' in that I think "Liberty Navy" and "Rachel Baker" need to be more blue and less gray/white.
Also: I'm not sure if it's possible, but if so I'd like to see it. Could you maybe make the girl more militant looking by like, changing the purple color of her outfit to some sort of dark green or dark blue color?
If it's not possible that's fine too, but I wouldn't mind seeing it if it is.