blending blending blending. The space stock and effects in the background are nice and clear, but they look like a completely separate entity than the render. Your render and bgs colors dont match and are not blending together.

I like the sparkles and effects, but i would suggest darkening and blurring the outter edges to create a clearer focal point.

not a big fan of the border... just personal opinion though.

overall you have some nice thoughts here, keep workin mate