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constructive criticism only please, any spam and/or flaming will not be tolerated ^^
Okay, I will try to give you real CnC.
To begin with, the background is empty, and the reason is the huge size you chose for the canvas. You should make it smaller and perhaps try to use C4Ds, brushes, if can you could use the smudge tool or add textures, patterns...
I like the way you made the sky, however I think it doesn't suit your render. Try using either anime renders with anime background or rape it with C4Ds.
The render doesnt blend well, which can be easily edited if you change the colors a bit and add more stuff around the focal. This would help you to add some depth too if you blur it a little bit.
I see there's some flow, but you should work more on it, but the things I said before would work.
Oh, get the text out of the corner, keep it simple and and closer to the focal.
Also, try using
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for the whole composition.