Heya. Interesting idea you have here .
If I would add my two cents... That wing splits image almost in half. Symmetrical composition is of course a matter of preferences but if you would like to break it a little, you could move it a bit to the left (let's say) and slant it slightly to enhance the effect. To balance the composition you cold stick on the opposite side of further plan some giant sword (let's say) slanted the opposite direction.
The other thing... I'm far from hating nudity but... I'm not sure if visible nipples will be at acceptable level of nudity for this challenge. But of course the final word belongs to the Judges so...
Just a thought, but maybe you could make her stony? You know - like after death in epic battle her body turned into stone. That could help to "keep gore and nudity to a SFW (safe for work) level" (quote from the Brief).
Of course it's all just my humble thoughts. If you see it different - just ignore me . Anyway... keep it up!