Depression, isolation, inadequacy and death are rather prominent themes in Evangelion, and this photograph portrays them in both atmosphere and color. Indeed, the use of color in this photograph is what makes it so striking.
The black, foreboding sky looms above as a grim harbinger of struggles ahead. The grey, derelict building represents obstacles, both physical and psychological, and is symbolic of an uncaring and increasingly empty world. Amid this bleak backdrop stands a fiery red Asuka, representing rage and defiance in both color and pose.
I am especially impressed by your outfit, which is nicely detailed and quite convincing. I can look at you and know immediately that you are cosplaying Asuka.
Also worthy of note is the use of size and scale. The building and sky tower imposingly over Asuka, and help reinforce the feeling of hopelessness as humanity fights against seemingly impossible odds.
However, this also highlights a flaw, as Asuka is a bit too small. If it wasn't for your bright red plugsuit, you would be easily missed. While the scale is good for symbolic reasons, the excess of empty space ends up hurting the picture.
Though flawed, the picture is still impressive and is evocative of Evangelion's post-apocalyptic world. Good work.