Here's some constructive criticism for you: This looks really dark, I mean REALLY dark. Feels like you multiplied the completed thing with a monochrome black layer with 50% opacity for some reason. Not sure if it has something to do with you setup's brightness, but the lack of tonal contrast hurts the piece quite bad. Try checking your levels to see what I'm talking about.
Composition is fine, I'm ok with it. I would've at least tried concealing character's bottom halves with something instead of just "stopping drawing" them though. That flaw becomes more apperent when you look at how Kerrigan's ribcage is suspended above Illidans wing tip and Arthas' cape and then the rest of her body just vanishes from existence, even though the right part of her torso should still be visible in the gap between the two objects right bellow.
Those are the two most obvious things that crossed my eye.
The quest marker is a nice touch.
Cheers m8. and gl.