This looks like quite a difficult piece!

Since this is taken from an animation, I'm guessing the forms in the original are made clear by the character's movement (or the "camera" movement). Given that you've got a still image, it might be a good idea to render the forms a bit more to give him volume, although the reason I say it's difficult is that the character himself appears to be emitting light, and he's also in space so it might be difficult to determine a light source to work from. The obvious choice is the galaxy at the bottom of the image, but lighting him strongly from below might look weird. If you did that, I'd be temped to extend the image further at the bottom so the galaxy is a bit more prominent. As it stands, I feel like the galaxy is compositionally very important but weirdly partly out of frame in the reference, although this could also be because this is just one frame taken from an animation.

What's working really well in your image is the cape, which I think looks great. I'd personally be tempted to diverge from the reference again and render it with more volume on the underside to really sell the idea that it's a fabric (or at least the equivalent of one), but the shape is really dynamic and you've captured the movement very well. I agree that altering the pose was a good idea, and I think yours looks stronger in this regard!